Process for the acetylation of chamigrenes

ABSTRACT

A- AND B- CHAMIGRENES WHEN TREATED WITH ACETIC ANHYDRIDE IN THE PRESENCE OF POLYPHOSPHORIC ACID YIELD THE NOVEL 4 -ACETO -6,8A-ETHANO-1,1,6-TRIMETHYL-1,2,3,5,6, 7,8,8A-OCTAHYDRONAPHTHALENE. THE NOVEL ACETYL COMPOUND THUS PRODUCED IS EXTREMELY USEFUL AS AN ODORANT AND FIXATIVE IN PERFUME COMPOUNDING.

United States Patent O1 hoe 3,754,037 Patented Aug. 21, 1973 3,754,037 PROCESS FOR THE ACETYLATION F CHAMIGRENES Garry C. Kitchens, Wayne, Alan R. Hochstetler, Bloomfield, and Kent Kaiser, Pequannock, N.J., assignors to Givaudan Corporation, Clifton, NJ. No Drawing. Filed Jan. '18, 1971, Ser. No. 107,472 Int. Cl. C07c 49/44 US. Cl. 260-587 2 Claims ABSTRACT OF THE DISCLOSURE ozand B- chamigrenes when treated with acetic anhydride in the presence of polyphosphoric acid yield the novel 4 aceto 6,8a-ethano-1,1,6-trimethyl-1,2,3,5,6, 7,8,8a-octahydronaphthalene. The novel acetyl compound thus produced is extremely useful as an odorant and fixative in perfume compounding.

FIELD OF THE INVENTION Process for preparing novel, acetylated, tricyclic,- olefinic C H hydrocarbons.

RELATED APPLICATIONS (1) Our copending application, Ser. No. 107,498 (U.S. Pat. No. 3,681,470) filed concurrently herewith entitled, Acid Isomerization of Thujopsene and Novel, Tricyclic, Olefinic C H Hydrocarbons Formed Thereby;

(2) Our copending application, Ser. No. 107,471 (U.S. Pat. No. 3,678,119) filed concurrently herewith entitled, Acid Isomerization of Chamigrenes; and

(3) Our copending application, Ser. No. 107,430 filed concurrently herewith entitled, 4-Aceto-6,8a-Ethano-1,1, 6 Trimethyl 1,2,3,5,6,7,8,8a Octahydronaphthalene, Process for Making Same and Compositions Containing Same.

DESCRIPTION OF THE PRIOR ART Perfume materials derived by the acetylation of the hydrocarbon fractions of cedarwood oil have been manufactured for over 15 years and sold under various trade names. The earlier products were derived by acetylating the hydrocarbons with acetic anhydride or acetyl chloride and catalysts such as aluminum chloride, zinc chloride or boron trifluoride. These products were essentially derived from the more stable a-cedrene (I) in the hydrocarbon fractions and were essentially acetylcedrene (II).

In recent years a perfume product has been manufactured by applying an acetylation procedure employing acetic anhydride and polyphosphoric acid to the hydrocarbon fractions of American cedarwood oil containing 40-50% a-cedrene (I), -l0% B-cedrene (III), 40-50% cisthujopsene (IV), (I. Runeberg, Acta. Chem. Scand., 15, 592 (1961)), 510% thujopsene isomers (G. Kitchens, J. Dorsky and K. Kaiser, A.C.S. Symposium on the Chemistry of Essential Oils. A.C.S. Meeting, New York, Sept. 9, 1969).

The known procedures for the isomerization of thujopsene (IV) with aqueous sulfuric acid (J. Tanaka and I. Yamashita, Bull, Osaka Ind. Research Inst., 9,5

(1958) aqueous oxalic acid, (S. Nagahama, Bull, Chem.

Soc. Japan, 33, 1467 (1960)) aqueous hydrochloric acid, (I. Tanaka and I. Yamashita, Bull. Osaka Ind. Research Inst., 9,5 (1958)) (L. E. Friedrich, Dissertation, 1966, University Microfilms, Inc. Ann Arbor, Mich., No. 67- 8559 p. 156) aqueous perchloric acid and dioxane (L. E. Friedrich, Dissertation, 1966, University Microfilms, Inc.,

Ann Arbor, Mich., No. 67-8559, p. 128) have been shown to yield mainly a hydrocarbon, 1,4,11,11-tetramethylbicyclo[5.4.0]undeca-3,7-diene (L. E. Friedrich, Dissertation, 1966, University Microfilms, Inc., Ann Arbor, Mich., No. 67-8559, p. 128) (X), which can be further isomerized with a catalytic amount of perchloric acid in acetic acid (L. E. Friedrich, Dissertation, 1966, University Microfilms, Inc., Ann Arbor, Mich., No. 67-8559 p. 51, -112) to the tricyclic hydrocarbon, 2,2,3,7- tetramethyltricyclo [5.2.2.0 undec-3-ene (XI) S. Ito (S. Ito, K. Endo, T. Yoshida, M. Yatagai and M. Kodama, Chem. Comm., 168(1967)) states fl-chamigrene (VII) was isolated as one of the major products from the hydrocarbon mixture either by the isomerization with oxalic acid or by the acid-catalyzed dehydration of widdrol. The references cited are Nagahama (S. Nagahama, Bull. Chem. Soc. Japan, 33, 1467 (1960)) andlDauben and Friedrich (W. G. Dauben and L. E. Friedrich, Tetrahedron Letters No. 38, 2675 (1964)). The authors cited above do not reveal the formation of jg-chamigrene (VH) by the isomerization of thujopsene SUMMARY OF THE INVENTION In our copending concurrently filed application Ser. No. 107,471 (U.S. Pat. No. 3,678,119) there is disclosed a method for isomerizing aand 5- chamigrenes to give novel tricyclic C H olefinic hydrocarbons, in particular 6,8a ethano 1,1,-trimethyl-1,2,3,5,6,7,8,8a-octahydronaphthalene. In the process of the present invention there is provided a. method for converting the chamigrenes into the 4-acetyl derivatives of the aforementioned octahydronaphthalene. In this process chamigrenes, either in the aor the ,8- form, or in a mixture comprising both, are treated with acetic anhydride in the presence of polyphosphoric acid. While the process of isomerization-withacetylation may be carried out in the absence of solvents, the presence of substantially anhydrous reaction-inert solvents, suitably chlorinated hydrocarbon solvents has been found desirable.

The 4 aceto 6,8a ethano-l,1,6-trimethyl-l,2,3,5,6, 7,8,8a-octahydronaphthalene produced in accordance with the present invention may also be prepared in accordance with the procedures set forth in our copending application Ser. No. 107,430, filed concurrently herewith. The compound produced in accordance with the present invention or in accordance with the disclosure of said cofiled and copending application is useful as an odorant and fixative for odorants and as such is most useful in the perfume compounding art, as is disclosed in detail in said copending application, Ser. No. 107,430.

DESCRIPTION OF PREFERRED EMBODIMENTS We have established in our laboratories that the aforementioned acetylated product derived from cedarwood oil hydrocarbons contains principally 40-55% acetylcedrene (II) derived from ocand ,B-cedrene and 40-50% acetylated C H hydrocarbons derived from thujopsene and thujopsene isomers. It has been further established by us that the portion of the product derived from the thujopsene-thujopsene isomers contains 7 isomeric C H .,COCH ketones. Six (22-26%) of these ketones, designated as isomers A, B, C, D, E, F, possess very weak woody odors and are not of practical interest in perfumery while the seventh ketone (18-24% 4-aceto-6,8a-ethano- 1,1,6 trimethyl 1,2,3,5,6 ,7,8,8a-octahydronaphthalene (V) designated as isomer G, is a new and novel compound possessing a powerful and valuable musk odor.

The reaction may be schematically represented as fol- 1966, University Microfilms, 1110., Ann Arbor, Mich, lows: No. 67-8559, p. 160) (XI).

CH (3-1353 j A B c CH CH CH W nwh (cH3cmzo H H PO CH 3 4 o 3 CH3 CH3 III CH +3 F CH CH 3 3 CH3 0 I CH CH3 C 3 1) \I' e3 VI V IV The structure of isomer D above was established as 4- This invention is also concerned with methods for the aceto-2,2,3,7-tetramethyltricycl0 [5.2.2.0 ]undec-3-ene preparation of pure 4-aceto-6,8a-ethano-1,1,6-trimethyl- (VI) by comparison with an authentic sample prepared 1,2,3,5,6,7,8,8a-octahydronaphthalene (V, isomer G) and from the hydrocarbon 2,2,3,7 tetramethyltricyclomixtures, rich in this ketone (V) and free of acetyl- [5.2.2.0 ]undec-3-ene (L. E. Friedrich, Dissertation, 40 cedrene (II) and mixtures with acetylcedrene (II) coni O l A B C i (CH co) 0 H PO (ll5%) VII VIII E F taining or more of the desired ketone (V) from thujopsene (IV) derived from naturally occurring essential oils as hibawood and cedarwood oils, fl-chamigrene (VII), a-chamigrene (VHI) and thujopsene isomers rich in the hydrocarbon, 6,8a-ethano-l,1,6-trimethy1-1,2,3,5,

Path A Path B I 2 & H+ l 5 6,7,8,8a-octahydronaphthalene (IX). The ketones derived by the acetylation of thujopsene (IV), chamigrenes (VII and VIII) or the tricyclic hydrocarbons (IX) are seven isomeric C H O ketones and are designated again as 35 isomers A to G.

This invention is also concerned with novel isomerization procedures utilizing protonating acids whereby thujopsene (IV) can be isomerized to B-chamigrene (VII) and a-chamigrene (VIII) or to a new series of tricyclic C H olefinic hydrocarbons rich in the hydrocarbon 6,8a-ethano-1,1,6-trimethyl 1,2,3,5,6,7,8,8a octahydronaphthalene (IX). The chamigrenes VII and VIII also can be isomerized by these novel procedures to the new series of tricyclic C H olefinic hydrocarbons (IX).

We have found unexpectedly that strong acids isomerize thujopsene (IV) by Path A to ocand fi-chamigrenes (VIII and VII) which in turn can be isomerized to a new series of tricyclic C H olefinic hydrocarbons, rich in the hydrocarbon, 6,8a-ethano-1,1,6-trirnethyl-1,2,3,5,6,7, 8,8a-octahydronaphthalene (IX), which we designate as hydrocarbons A and B while weak or dilute aqueous acids follow a difierent isomerization (Path B) to yield the hydrocarbon, 1,4,11,1l-tetramethylbicyclo[5.4.0]undeca-3,7-diene (X) (L. E. Friedrich, Dissertation, 1966,

University Microfilms, Inc., Ann Arbor, Mich., No. 67-

8559, p. 128) which can be further isomerized to the hydrocarbon 2,2,3,7 tetramethyltricyclo[5.2.2.0 ]undec-3-ene (X1) (L. E. Friedrich, Dissertation, 1966, University Microfilms, Inc., Ann Arbor, Mich., No. 67- 8559, p. 51,

+ other 15 24 tricyclic hydrocarbons VIII (hydrocarbons A and B) minor 0 E1 tricyclic hydrocarbons Our invention concerns novel procedures using strong acids, such as formic acid or a mixture of acetic acid and such acids as oxalic, sulfuric, phosphoric, polyphosphoric, toluenesulfonic and perchloric acids to yield the hydrocarbons of Path A as the major products of the reaction. The tricyclic hydrocarbons of Path A are new and valuable raw materials for conversion to valuable perfume materials.

Another object of this invention is a novel method for the separation of the hydrocarbons from cedarwood oils. There is no known chemical method for the separation of the cedrenes from thujopsene in cedarwood hydrocarbon fractions. The separation by distillation is extremely difficult and uneconomical due to close boiling points. By applying our novel isomerization to cedarwood hydrocarbons containing 40-50% u-cedrene (1), 5-10% 5- cedrene (III), 4050% cis-thujopsene (IV), 5l0% thujopsene isomers, the a-cedrene (1) remains unaltered while ,B-cedrene (III) is isomerized to u-cedrene (I) and thujopsene (IV) is isomerized either to the chamigrenes (VII and VIII) or the new tricyclic series of hydrocarbons A and B (IX). The a-cedrene (I) is now easily separated by distillation in high purity from the chamigrenes or tricyclic hydrocarbons since the latter have higher boiling points.

III

in ketone (V) and free of acetylcedrene (II) and mixtures with acetylcedrene (II) containing 40% or more of VIII + other tri- 915 .24

hydrocarbons hydrocarbons A and B One method for the preparation of the ketone (V) involves the acetylation of thujopsene (IV) using acetic anhydride and polyphosphoric acid (115%) to yield a 15 mixture of isomeric C H O ketones A, B, C, D (VI),

E, F and G (V), rich in the ketone V) (isomer G).

CH CH CH 3 CH 3 (CH3CO)20 3 A+B+C+ CH +E+F+ H PO 3 4 c1 1 CH CH 3 CH3 CH3 IV D G VI V the ketone (V) from thujopsene (IV) (derived from thujopsene containing essential oils (T. Norin, Acta Chem. Scand., 15, 1667 (1961) such as hibawood oil and American cedarwood oil), and from the thujopsene isomers, a-chamigrene (VIII), p-chamigrene (VII) and tricyclic C H hydrocarbons A and B rich in the hydrocarbon 6,8aethano-1,1,6-trimethy1-1,2,3,5,6,7,8,8a-0ctacan on;

CH3 CH3 VII VI I:

hydronaphthalene (IX). This invention is also concerned with novel isomerization procedures for isomerizing thujopsene (IV) to B- and u-chamigrenes (VII and VIII) and to tricyclic C H olefinic hydrocarbons A and B rich in the tricyclic olefinic hydrocarbon 6,8a-ethan0- 1,1,6-trimethyl 1,2,3,5,6,7,8,8a octahydronaphthalene (IX).

A second method for the preparation of ketone (V) (isomer G) involves the acetylation of 5- and achamigrenes (VII and VIII) (derived by the formic acid isomerization of thujopsene) using acetic anhydride and polyphosphoric acid to also yield a mixture of isomeric C H O ketones A, B, C, D (VI), E, F and G (V), rich in the desired ketone (V) (isomer G).

A third method for the preparation of the ketone (V) involves the acetylation of tricyclic C H olefinic hydrocarbons A and B rich in the hydrocarbon (IX), (derived by the isomerization of thujopsene with a mixture of polyphosphoric acid and acetic acid) using acetic anhydride and polyphosphoric acid to yield a mixture of isomeric ketones A, B, C, D (VI), E, F and G (V) rich in the desired ketone (V) (isomer G).

CH CH (cH co) o C H PO tricyclic hydrocarbons A and B The reactions conditions for the above acetylations are not critical. The acetic anhydride can be varied between IV X 1.0 and 10.0 moles per mole of hydrocarbon. We prefer to use 2.0-4.0 moles of acetic anhydride per mole of the hydrocarbon.

The polyphosphoric acid (115 H PO can be widely varied from 1.0-5.0 moles calculated as P per mole of hydrocarbon. We prefer to use 1.4-2.82 moles (as P 0 per mole of hydrocarbon.

The reaction can be conducted at a temperature of to 100 C. At low temperatures the reaction mixture is viscous and agitation is difficult. At high temperatures the yields are low and undesirable byproducts are formed. We prefer to conduct the reaction between to C.

The reaction can be conducted with or without solvents. Solvents such as acetic acid, chloroform, carbon tetrachloride, ethylene dichloride, methylene dichloride, cyclohexane, hexane, heptane, benzene and toluent can be used. If a solvent is used, we prefer to use ethylene dichloride or methylene dichloride in the amount of 0.5 to 1.5 times the Weight of the hydrocarbon.

In the above third method for preparation of the ketone (V) (isomer G) the acetylatiou can be accomplished by the use of acetic anhydride and boron trifluoride catalyst instead of polyphosphoric acid catalyst. The conditions for this reaction are the same as the above acetic anhydride-polyphosphoric acid reaction except a molar excess of boron trifiuoride per mole of hydrocarbon is required for complete conversion. We prefer to use 1.1-1.25 moles of BF per mole of the hydrocarbon.

The novel isomerization of this invention involves the isomerization of thujopsene (IV) with strong concentrated protonating acids to form as the major products fi-chamigrene (VII) and u-charnigrene (VIII) or a new series of tricyclic C H olefins, hydrocarbons A and B, rich in 6,8a-ethano-l, 1,6 trimethyl 1,2,3,5,7,8,8a-octahydronaphthalene (IX) (Path A) rather than the hydrocarbons 1,4,l1,ll-tetramethylbicyclo[5.4.0]undeca 3,7-

I l I I VII VIII V diene (X) or 2,2,3,7-tetramethyltricyclo[5.2.2.0 ]undec- 3-ene (XI) (Path B).

+ other tricyclic hydrocarbons hydrocarbons A and B other C H tricyclic hydrocarbons The tricyclic C H hydrocarbons of Path A are new compounds and are valuable intermediates in the preparation of novel perfume materials while the tricyclic hydrocarbons of Path B are known (L E. Friedrich, Dissertation 1966, University Microfilms, Inc., Ann Arbor, Mich. No. 67-8559, p. 51, 160) and are not intermediates for perfume materials.

We have found that strong concentrated protonating acids (with a pKa of 4.0 or smaller) such as formic, sulfuric, phosphoric, polyphosphoric, toluenesulfonic, and perchloric acids favor the isomerization of thujopsene (IV) by Path A while dilute aqueous acids favor the isomerization of thujopsene (IV) by Path B. We have also found that the isomerization by Path A is further favored by the use of mixtures of acetic acid and strong acids as oxalic and the above mentioned strong acids. Other alkanoic organic acids, RCOOH, Where R is an alkyl group containing 1 to 5 carbon atoms can be used in place of the acetic acid, however we prefer to use acetic acid.

The isomerizations can be conducted in the presence of solvents such as methylene dichloride, ethylene dichloride, carbon tetrachloride, chloroform, ether and dioxane, however, we prefer not to use solvents. The product of the isomerization by Path A depends on the acid, acid concentration, temperature and reaction time. Thus by the selection of the proper acid and conditions either the chamigrenes (VII and VIII) or the tricyclic hydrocarbons A and B of Path A, or a mixture of these hydrocarbons can be obtained as the major products of the isomerization.

In general, concentrated acids containing 50% or lss water can be used for the isomerizations, however, the more concentrated acids of -100% concentration are more favorable to yield the hydrocarbons of Path A.

In general, for the isomerization of the thujopsene (IV) to predominatelyform the chamigrenes (VII and VIII) strong acids, or a mixture of acetic acid and strong acids with a pKa of 2-4, can be used. For the isomerization of thujopsene (IV) or the chamigrenes (VII and VIII) to the tricyclic hydrocarbons (IX) of Path A stronger acids with a pKa of 0.85 or less are required. Intermediate acid strengths give a greater mixture of chamigrenes and tricyclic hydrocarbons.

In general, the quantity of acids used in the isomerization is diiferent for each acid used, there being a lower limit whereby the isomerization does not occur or does not go to completion due to the reaction of the catalyst with the hydrocarbon. These limits can be established only by experimental data. In some cases the use of large excess quantities of isomerization acids leads to low yields as a result of side reactions.

For the isomerization of thujopsene (IV) to the chamigrenes (VII and VIII) we prefer to use formic acid or a mixture of acetic acid and formic, oxalic, phosphoric or polyphosphoric acids.

Various concentrations of formic acid (50-l00%) can be used, however, to avoid undesirable side reactions we prefer to use 90100% formic acid. The amount of formic acid is not too critical, 3-l00% by weight based on the weight of thujopsene (IV) or even greater quantities which are not economically feasible can be used. We prefer to use 10-20% by weight of 90-98% formic acid based on the weight of thujopsene (IV).

The temperature of the reaction is not critical and can be carried out in the range of 40-150" C. At the lower temperatures the reaction is slow, while above 100 C. pressure vessels must be used and undesirable side reactions occur. We prefer to use a temperature of 90-100" C. The isomerization is usually complete within /6 to 3 hours.

In the isomerization of thujopsene (IV) to chamigrenes (VII and VIII) using mixtures of acetic acid and formic acid, mixtures containing 20 mole percent or more formic acid can be used. We prefer to use a mixture containing 40 to 60 mole percent of formic acid. The quantity of the acid mixture is not too critical; however, we prefer to use 20% to 50% by weight of the acid mixture based on the weight of the thujopsene (IV). The isomerization can be carried out in a temperature range of 40150 C. We prefer to conduct the isomerization between 90-100 C. The isomerization under the preferred condition is usually complete in 3 to 4 hours.

For the isomerization of thujopsene (IV) to the chamigrenes (VII and VIII) neither acetic acid nor oxalic acid are suitable catalysts for the isomerization; however, mixtures of oxalic and acetic acid are good catalysts. The conditions for the isomerization using mixtures of oxalic and acetic acids are very critical. Mixtures containing 4.0 to 10 mole percent oxalic acid can be used. We prefer to use mixtures containing 4.5 to 6 mole percent of oxalic acid. The amount of the acid mixture used can be widely varied from 5% to 100% by weight based on the thujopsene (IV); however, to achieve the highest yields we prefer to use 10 to 20% by weight based on the thujopsene (IV). The reaction can be conducted between 50 and 150 C. We

prefer to carry out the reaction at 90-100 C. The reaction is complete in 3 to 4 hours using the preferred conditions.

In general, for the isomerization of thujopsene (IV) to the chamigrenes (VH and VIII) using very strong acids such as phosphoric acid, polyphosphoric acid, sulfuric acid, and perchloric acid, mixtures of acetic and these acids can be used. The concentration of the acetic acid mixtures is very important because at high concentrations of these acid mixtures the chamigrenes (VH and VIII) can be further converted to the tricyclic hydrocarobns A and B (IX) of Path A. In general, the acetic acid mixtures containing an acid having a pKa of about 2.0 or larger can be used. Acetic acid, mixtures of these strong acids containing 0.1 to 6.0 mole percent of the strong acids and isomerization temperatures of 10 to 120 C. can be used.

For the strong acid isomen'zations, we prefer to use an acetic acid-polyphosphoric acid mixture containing 0.7 to 5.5 mole percent of polyphosphoric acid and a temperature of 30 to 60 C. The amount of the mixed acid used for the isomerization can be widely varied from 10 to 200% by weight based on the thujopsene (IV), with to being the preferred amounts. The isomerizations under the preferred conditions are usually complete in 3 to 6 hours.

For the complete isomerization of thujopsene (IV) to the tricyclic hydrocarbons A and B (IX) of Path A mixtures of acetic acid and strong acids as phosphoric acid (100% polyphosphoric acid, sulfuric acid and perchloric acid with a pKa of about 0.85 or smaller are required. For the greatest selectivity we prefer to use acetic acid mixtures of polyphosphoric acid. Acetic acid mixtures containing 5.5 to 50 mole percent of polyphosphoric acid can be used. The preferred acetic acid mixture is 10 to 30 mole percent of polyphosphoric acid. An isomerization temperature of 20 to 60 C. can be used; however, a temperature of 40 to 50 C. is preferred. The amount of isomerizing acid can be widely varied, 10-500% by weight based on the thujopsene (IV); however, a 50150% by weight is preferred. The isomerization is usually complete in 3 to 6 hours using the preferred conditions.

'For the isomerizations of the chamigrenes (VH and VIII) to the tricyclic hydrocarbons A and B (IX) we prefer to use mixtures of acetic acid and polyphosphoric acid under the same conditions as above for thujopsene (IV).

In the isomerization of the chamigrenes (VII and VIII), mixtures of acetic, and other strong acids, such as sulfuric and perchloric acids can be used instead of the acetic and polyphosphoric acid mixture. The conditions are approximately the same as for the latter acid mixtures.

In the application of our above novel isomerization procedures to the hydrocarbon portions of cedarwood oil, u-cedrene (I) is unaltered; B-cedrene (III) is isomerized to wcedrene (I), thujopsene (IV) is isomerized to either the chamigrenes (VII and VIII) or the new tricyclic hydrocarbons A and B (IX). The constituents are now easily and economically separated by vacuum distillation. The chamigrenes (VII and VIII), and tricyclic hydrocarbons A and B, rich in 6,8a-ethano-l,1,6-trirnethyl-l,2,3,5,6,8,8aoctahydronaphthalene (IX), are valuable raw materials for the preparation of our novel 4-aceto6,8a-ethano-l,l,6- trimethyl-1,2,3,5,6,7,8,8a-octahydronaphthalene (isomer G), (V) of this invention. The isomerization conditions are identical to those above for isomerizing thujopsene (IV) to either the chamigrenes (VII and VIII) or to the tricyclic olefin hydrocarbons A and B (IX).

4-aceto-6,8a-ethano-1,1,6-trimethyl-1,2,3,5,6,7,8,8a-octahydronaphthalene (V), (isomer G), possesses a very intense amber, woody and musk odor. The material with its amber-like note is reminiscent of ambergris but more tenacious and sweeter. 'Isomer G (V) when compared in strength and tenacity with ambergris is found to be approximately three times stronger than ambergris and to last ten times longer. Isorner G (V), besides contributing unique odor characteristics to perfume compositions, has unusual fixative properties which may be compared to ambergris, a long established and superb fixative.

Mixtures of isomer G (V) and the other isomeric ketones, isomers A-F, derived from the thujopsene (IV) and mixtures of isomer G (V), isomers A-F and acetylcedrene (II) derived from thujopsene (IV) and cedrene (I) which contain 40% or more of isomer G (V) exhibit the above unique olfactory and fixture properties. In mixtures where the concentration of isomer G (V) is below 40%, the olfactory and fixative properties drop off rapidly and its full potential as an odorant and a fixative is not fully realized.

Isomer G (V) and the mixtures above containing 40% or more of isomer G (V) are fine odorants and fixa- 13 tives which improve and render more desirable many types of fragrances. These materials can be used in the same manner as ambergris in formulations for amber notes and fixative properties.

EXAMPLES Instrumentation in the following examples is as follows:

(A) Vapor phase chromatography (v.p.c.)

A-l. 150 C., 60 ml./min., 15% carbowax 20 M on chromosorb P, A" dia., Z-meter copper column.

A2. 225 C., 60 ml./min., 15% carbowax 20 M on chromosorb P. 4" dia., 2-meter copper column.

A-3. 150 C., 40 p.s.i., S.C.O.T. (support coated open tubular) 3% carbowax, 0.02" dia., 50' stainless steel column purchased from Perkin-Elmer Corp., Norwalk, Conn.

A-4. 90180 C., 6-8 ml./min., program 2.8 C./min., S.C.O.T. support coated open tubular), 3% carbowax 20 M, 0.02" dia., 50' stainless steel column purchased from Perkin-Elmer Cor-p., Norwalk, Conn.

(B) V.p.c./ mass spectrum Perkin-Elmer 900, S.C.O.T 3% carbowax 20 M, 0.02" dia., 50' stainless steel column/Perkin-Elmer 270 (double focusing) on-line to a Varian 620/i.

(C) Infrared absorption (IR) Perkin-Elmer 457 (D) Nuclear magnetic resonance (NMR) Varian A60A (E) Nestor/Faust NFA-IOO auto annular Teflon spinning band distillation column purchased from Nester/ Faust Manufacturing Corp., Newark, Del.

EXAMPLE 1 Tricyclic C H hydrocarbons rich in 6,8a-ethano-1,l,6- trimethyl-l,2,3,5,6,7,8,8a-octahydronaphthalene (IX) Into a reaction flask, equipped with an agitator, thermometer, feeding funnel and a condenser, is charged 500 g. glacial acetic acid and 200 g. polyphosphoric acid (115%). The mixture is agitated and 500 g. thujopsene (IV) is fed in at 40 C. over a Sminute period. The batch is agitated at 40 C. for 3 hours and poured onto 1000 g. water. The oil layer is separated and the aqueous layer extracted 2x 100 ml. benzene. The combined oil and benzene extracts are washed 2X 50 ml. water, made alkaline with sodium carbonate and washed neutral with salt water. The benzene is distilled 011 under reduced pressure leaving 505 g. crude hdyrocarbons. v.p.c. (A-l) of the crude shows eight components: (1) 0.4%, (2) 1.3%, (3) 4.7%, (4) 4.9%, (5) 9.3%, (6) 27.3%, (7) 44.5%, (8) 7.5%. Components 14 are tricyclic C H hydrocarbons of unknown structure. Components 5 is 2,2,3,7 tetramethyltricyclo[5.2.2.O ]undec 3-ene (XI). Components 6 and 7 are the desired tricyclic C H hydrocarbons and are referred to as hydrocarbons A and hydrocarbons B (IX). Component 8 is chamigrenes (VII and VIII), principally a-chamigrene (VIII).

The crude is vacuum distilled at 0.5 mm. using a 2 ft., 25 mm. diameter Goodloe packed column (rated 14 theoretical plates) and a reflux ratio of :1 and the following fractions are collected:

(1) 66.0 g.; B.P. 5l-65 C./0.5 mm.; n 1.4980; v.p.c. (A-l): 8.2% hydrocarbon A: 3.2% hydrocarbon B.

(2) 85.5 g.; B.P. 6566 C./0.5 mm.; 11 1.5045; v.p.c. (A-l): 35.4% hydrocarbon A, 21.6% hydrocarbon B.

(3) 262.4 g.; B.P. 66-76 C./0.5 mm.; n 1.5075; Sp. Gr. C./25 C. 0.9442; v.p.c. (A-l): 32.9% hydrocarbon A; 59.7% hydrocarbon B; 3.3% u-chamigrene (VIII).

(4) 32.0 g.; B.P. 76-89 C./0.5 mm.; n 1.5150; v.p.c. (A-l): 24.6% hydrocarbon B, 47.2% a-chamigrene (VIII), 28.4% esters (formates).

(5) 10.5 g.; B.P. 89-90 C./0.5 mm.; n 1.5184; v.p.c. (A-l): 10.6% a-chamigrene (VIII), 89.4% formates.

(6) 35.1 g. residue.

The redistillation of fractions 1,2 and 4 will give more material similar to fraction 3, the desired products of the reaction.

Samples of hydrocarbons A and B are prepared from fraction 2 above by vacuum distillation at 5 mm. using a Nestor/Faust column (B) and preparative vapor phase chromatography. The following is analytical data for the hydrocarbons:

Hydrocarbons A Calcd. for C H C, 88.16%; H, 11.84%. Found: C, 88.24%; H, 11.81%.

Mass spectrum (B): 204 mol. Wt. (31%), 189 (27%), 175 (100%), 161 (8%), 148 (18%), 147 (13%), 133 (20%), 119 (353%), 105 (39%), (20%), 43 (16%), 91 (24%), 81 (18%), 79 (17%), 77 (15%), 69 (8%), 67 (11%), 65 (7%), 55 (16%), 53 (10%), 43 (7%), 41 (33%).

NMR (D) (1', ODCl centered at 4.75 (1H, broad, /2H= 10 I-Iz., multiplet, vinylic), centered at 7.93 (2H, multiplet, allylic), centered at 8.08 (2H, multiplet, allylic), 8.25-8.92 (10H, multiplet, methylene), 9.00 3H, singlet, methyl H); 9.13 (3H, singlet, methyl H), 9.17 (3H, singlet, methyl H);

IR (C) (v, neat max.): 2930 (s.), 2910 (s.), 2850 (s.), 1664 (w.), 1550 (s.), 1383 m.), 1372 (w.), 1367 (m.), 1258 (w.), 1188 (w.), 1102 (w.), 985 (w.), 960 (w.), 840 (m.), 795 (w.), 662 w.), cm.-

Hydrocarbons B Calcd. for C H C, 88.16%; H, 11.84%.

Found: C, 88.07%; H, 11.76%.

Mass spectrum (B): 204 mol. wt. (42%), 189 (40%), 175 161 (11%), 148 (25%), 147 (23%), I133 (25%), 1119 (50%), 107 (17%), (55%), 95 (25%), 93 (20%), 91 (29%), 81 (20%), 79 (20%), 77 (16%), 69 (9%), 67 (13%), 65 (9%), 55 (21%), 53 (11%), 43 (6%), 41 (34%).

NMR (D) (1', CDCI centered at 4.72 (1H, broad, vinylic H), 8.04 (4H, broad multiplet, allylic H), 8.25- 8.83 (10H, multiplet, methylene H), 9.19 (3H, singlet, methyl H), 9.21 (6H singlet, methyl H).

IR (C) (v, neat, max.): 2945 (s.), 2920 (s.), 2865 (s.), 1670 (W.), 1458 (s.), 1440 (m.), 1385 (m.), 1376 (m.), 1365 (m.), 1345 (w.), 1135 (w.), 1070 (w.), 960 (w.), 838 (w.), '815 (w.), 770 (w.) cm.

EXAMPLE 2 B- and a-chamigrenes (VII and VIII) Into a reaction flask, equipped with an agitator, thermometer and a condenser, is charged 200 g. thujopsene (IV) and 20 g. of 90% formic acid. The batch is heated to 100 C. and agitated at 100 C. for 1 hour. 100 m1. of water is added and allowed to settle. The oil layer is separated and the aqueous layer extracted 2X50 m1. of benzene. The combined oil and benzene extracts are washed 2X50 ml. of water, neutralized with 10% sodium bicarbonate and washed with 50 ml. of water. The benzene is distilled off under reduced pressure leaving 200 g. of crude hydrocarbons. v.p.c. (A-1) of the crude shows seven components: (1) 0.7 (2) 2.8%, (3) 2.8%, (4) 1.9%, (5) 4.7%, (6) 25.1%, (7) 67.0%. Components 1 and 2 are hydrocarbons of unknown structures, component 3 is 2,2,3,7-tetramethyltricyclo[5.2.2.0 ]-undec-3-ene (XI). Components 4 and 5 are-the tricyclic hydrocarbons A and B (IX) of Example 1. Components 6 and 7 are the desire fian a-chamigrenesWH an VH-I).

The crude is vacuum distilled at 0.5 mm. using a 37 cm., 25 mm. dia. column packed with glass helices and the following fractions are collected:

(1) 14.9 g.; B.P. 60-68 C./0.5 mm.; r1 1.5081; v.p.c. (A -1): 26.1% B-chamigrene (VII); 41.7% a-chamigrene (VIII).

(2) 36.3 g.; B.P. 68-69 C./0.5 mm.; a 1.5106; v.p.c. (A-l): 29.4% fl-chamigrene (VII); 50.8% a-chamigrene (VIII).

(3) 131.8 g.; B.P. 69 C./0.5 mm.; n 1.5128; sp. gr. 25 C./25 C. 0.9340; v.p.c. (A-l): 25.4% B-chaanigrene (VII); 66.9% a-chamigrene (VIH).

(4) 9.0 g.; B.P. 69-79 C./0.5 mm.; n 1.5158; v.p.c. (A-l): 8.5% B-chamigrene (VII); 81.4% a-chamigrene (VIII).

(5) 6.0 g. residue.

The redistillation of fractions 1, 2 and 4 will give more material similar to fraction 3, the desired products of the reaction.

The product of the reaction contains 7.8% of 1,4,11,11- tetramethylbicyclo[5.4.0]undeca-3,7-diene (X) (L. E. Friedrich, Dissertation, 1966, University Microfilms, Inc., Ann Arbor, Mich, No. 67-8559, p. 128) which is difiicult to detect as it has the same retention time by v.p.c. (A-1) as a-chamigrene (VIII). v.p.c. (A-4) shows this component as a shoulder in the main peak (a-chamigrene). Isomerization of a small sample of the chamigrenes according to Example 1 converts compound X to the known 2,2,3,7-tetramethyltricycld[5.2.2.0 lundec-3-ene (L. E. Friedrich, Dissertation, 1966, University Microfilms, 1110., Ann Arbor, Mich., No. 67-8559, p. 51, 1960) (XI) and the chamigrenes to the tricyclic hydrocarbons A and B (IX) of Example 1. The components are now analyzed by v.p.c. (A-l).

Pure samples of B- and a-chamigrenes (VII and VIII) are prepared by vacuum distillation at 5 mm. using a Nester/=Faust distillation column (B), followed by preparative vapor phase chromatography. The following is the analytical data for the pure materials.

B-chamigrcne (VII) Calcd. for C I-I C, 88.16%; H, 11.84%.

Found: C, 88.31%; H, 12.00%.

Mass spectrum (B): 204 mol. wt. (26%), 189 (79%), 175 (11%), 161 (28%), 148 (21%), 147 (2 0%), 145 (11%), 135 (20%), 133 (45%), 131 (15%), 121 (55%), 119 (60%), 109 (25%), 107 (65%), 105 (72% 95 (36%), 94 (44%), 93 (100%), 92 (22%), 91 (69%), 81 (38%), 79 (59%), 77 (39%), 69 (44%), 67 (35%), 65 (20% 55 (55% 43 (30%), 41 (94%).

NMR (D) (-r, CD01 centered at 4.73 (1H, broad multiplet, vinylic *H), 5.17 (1H, doublet, J =2 Hz., methylenic H), 5.50 (1H, doublet, I=2 Hz., methylenic H), 7.27-8.27 (6H, multiplet, allylic H), 8.258.8 6H, multiplet, methylene H), 8.43 (3H singlet, methyl H), 9.13 (3H, singlet, methyl H), 9.18 (3H, singlet, methyl H).

1R (C) (v, neat, max.): 2910 (s.), 2860 (s.), 1630 (m.), 1435 (s.), 1382 (m.), 1362 (m.), 1150 (w.), 1010 (w.), 885 (s.), 797 (w.) cmr u-chamigrene (VIII) Calcd. for C H C, 88.16%; H, 11.84%.

Found: C, 79.98%; H, 11.96%.

Mass spectrum (B): 204 mol. wt. (38%), 189 (12% 175 (2%), 161 (14%), 148 (8%), 147 136 (82%), 134 (15%), 1'33 (36%), 121 (100%), P19 (74%), 107 (27%),105 (44%), 93 (58%), 91 (411%), 80 (21%), 78 69 (12%), 67 (10%), 65 (9% 55 (27%),43 (12%), 41 (39%).

NMR (D) (1', CDCI 4.59 (2H, broad multiplet, vinylic H), 7.758.l3 (6H, multiplet, allylic H), 8.1-7- 8.75 (4H, multiplet, methylene H), 8.33 (6H, singlet, vinylic methyl H), 9.12 (3H, singlet, methyl H), 9.15 (3H, singlet, methyl H).

IR (C) (v, neat, max): 2920 (s.), 2840 (s.), 1655 (W-), 1450 (s.), 1388 (s.), 1380 (s.), 1368 (s.), 1340 (w.), 1320 (W.), 1220 (w.), 1190 (w.), 1160 (w.), 1150 (w.), 1130 (W.), 1088 (m.), 1072 (m.), 1030 (w.), 1020 (w.), 980 (w.), 955 (w.), 942 (w.), 830 (s.), 810 (s.), 800 (m.), 760 (w.) GEL A, cyclohexane, max 192.5 nm. (e 15,000).

EXAMPLE 3 Tricyclic C H hydrocarbons, rich in 6,8-ethano-1,1,6-

trimethyl-1,2,3,5,6,7,8,8a-octahydronaphthalene (IX), from cedarwood hydrocarbons 2090 g. of Texas cedarwood oil (c.v. 22.6; sp. gr. 0.9483; a 1.5040; [a] j=52) is distilled with a 37 cm. glass helix column at a pressure of 0.6 mm. After a forerun of 2 8 g. (B.P. 45-82 C.), one obtains 1579 g. hydrocarbon fractions, B.P. 83102 C., 11 1-.5038; sp. gr. at 25 C. 0.9361, [a] =59. By gas chromatogram, these hydrocarbon fractions contain 37.9% acedrene, 9% fi-cedrene, 41.0% thujopsene, and 9.4% thujopsene isomers.

Into a reaction flask, equipped with an agitator, thermometer, feeding funnel and a condenser is charged, while agitating, 1000 g. acetic acid and 400 g. polyphosphoric acid The temperature is adjusted to 40 C. and 1000 g. of the above hydrocarbon fractions, is fed in at 40 C. over a 10-minute period. The batch is agitated at 40 C. for 3 hours and poured onto 1000 g. of agitated ice water. The layers are allowed to separate and the aqueous layer is extracted 3X50 ml. benzene. The combined oil and benzene extracts are washed with 2 X50 ml. water, made alkaline with 10% aqueous sodium carbonate and washed neutral with salt water. The benzene is removed by distillation under slightly reduced pressure leaving 1000 g. of crude hydrocarbons, which analyze by v.p.c. (A-l) as follows: six components, (1) 2.4%, (2) 48.9%, (3) 7.6%, (4) 14.4%, (5) 21.5%, (6) 5.1%. Component 1 is a C H hydrocarbon of unknown structure, component 2 is ot-cedrene (I), component 3 is 2,2,3,7-tetrameth yltricyclo[5.2.2.0 ]undec-3-ene (XI), components 4 and 5 are the desired tricyclic hydrocarbons A and B (IX) and component 6 is a-chamigrene (VIH).

The crude is vacuum distilled at 0.5 mm. without fractionation using a '37 cm. column packed with glass helices to give 938 g. of hydrocarbon (B.P. 6386 C./0.5 mm.) distillate and 57.0 g. of residue. The hydrocarbon distillate is redistilled at 0.5 mm. using a 2-ft. (25 mm. diameter) Goodloe packed column (rated 14 theoretical plates), using a reflux ratio of 20: 1 and the following fractions are collected:

1) 123.2 g.: B.P. 56-68 C./0.-5 mm; n 1.4974; v.p.c. (A-l): 18.7% consisting of three unknown hydrocarbons, 81.3% a-cedrene (I).

(2) 289.6 g.: B.P. 68-70 C./0.5 mm.: n 1.4988; v.p.c. (A-l): 2.3% unknown hydrocarbon, 87.1% Otcedrene (I), 7.6% hydrocarbon A, 3.2% hydrocarbon B.

(3) 115.5 g.: B.P. 70-72" C./0.5 mm.: 22 1.5010; v.p.c. (A-l): 67.2% a-cedrene, 14.3% 2,2,3,7-tetramethyltricyclo[5.2.2.0 ]undec-3-ene (XI), 13.7% hydrocarbon A, 4.8% hydrocarbon -B.

(4) 112.1 g.: B.P. 72 C./0.5 mm.: n 1.5065; sp. gr. 25 C./25 C. 0.9422; v.p.c. (A-l): 17.9% a-cedrene (I), 13.7% 2,2,3,7 tetramethyltricyclo[5.2.2.0 ]undec-3-ene (XI), 42.2% hydrocarbon A, 26.5% hydrocarbon B.

(5) 196.8 g.: B.P. 72-74 C./0.5 mm.: 11 1.5095; sp. gr. 25 C./25 C. 0.9433: v.p.c. (A-1): 27.1% hydrocarbon A, 65.6% hydrocarbon B, 7.3% oz-chamigrene (VIII).

(6) 60.7 g.: B.P. 74-82 C./0.5 mm.: 11 1.5160; v.p.c. (A-l): 36.7% hydrocarbon B, 39.2% a-chamigrene (VIII), 24.1% cuparene and acetates.

(7) 30.0 g. residue.

Redistillation of fractions 2, 3, 4 and 6 will give an additional material similar to fraction 5, the desired tricyclic hydrocarbons A and B (IX).

1 7 The hydrocarbons A and B can be separated from fraction as described in Example 1. The ir, mnr, and mass spectral date are identical to that given for hydrocarbons A and B in Example 1.

EXAMPLE 4 8- and a-chamigrenes (VII and VIII) from cedarwood hydrocarbons Into a reaction flask, equipped with an agitator, thermometer and a condenser is charged 1,500 g. of hydrocarbon fractions obtained in accordance with Example 3 and 150 g. 90% formic acid. The batch is agitated and heated over a one-half hour period to 100 C. and agitated for 1 hour at 100 C. 200 ml. of water is added and the batch is allowed to settle. The oil layer is washed 2X50 ml. of water, made alkaline using aqueous sodium carbonate and washed neutral with salt water. The crude oil, 1500 g. analyzes by v.p.c. (A-l) mainly as seven components: (1) 1.0%, (2) 44.2%, (3) 6.5%, (4) 1.9%, (5) 3.7%, (6) 12.0%, (7) 30.7%. Component 1 is a hydrocarbon of unknown structure, component 2 is orcedrene (I), component 3 is 2,2,3,7-tetramethyltricyclo [5.2.2.0 ]undec-3-ene (XI), components 4 and 5 are the hydrocarbons A and B (IX) of Example 1, and components 6 and 7 are the desired 8- and u-chamigrenes (VII and VIII).

The crude material is purified by vacuum distillation at 0.5 mm. using a 4-ft. (25 mm. dia.) Goodloe packed column (rated 28 theoretical plates) and a reflux ratio of 5:1 and the following fractions are collected:

(1) 27.9 g.: B.P. 43 61" C./0.5 mm.: n 1.4980; v.p.c. (A-l): 25.6% consisting of eight light unknown hydrocarbons, 68.9% a-cedrene (I), 4.8% 2,2,3,7-tetramethyltricyclo [5.2.2.0 ]undec-3-ene (XI).

(2) 606.0 g.: B.P. 61-69 C./0.5 mm.: n 1.4985; v.p.c. (A-l): 1.8% unknown hydrocarbon, 90.7% acedrene (I), 7.5% 2,2,3,7-tetramethyltricyclo[5.2.2.0 undec-B-ene (XI).

(3) 80.9 g.: B.P. 60 C./0.5 mm.: 12 1.5010; v.p.c. (Al): 62.5% a-cedrene, 13.7% 2,2,3,7-tetramethyltricyclo[5.2.2.0 ]undec-3-ene (XI), 6.8% hydrocarbon A (Example 1), 5.6% hydrocarbon B (Example 1), 7.8% fi-chamigrene (VII), 3.6% a-chamigrene (VIII).

(4) 108.2 g.: B.P. 6972 C./0.5 mm.: n 1.5085; v.p.c. (A-l): 16.7% u-cedrene (I), 4.8% 2,2,3,7-tetramethyltricyclo[5.2.2.0 ]undec-3-ene (XI), 8.6% hydro carbon A (IX) (Example 1), 14.5% hydrocarbon B (IX) (Example 1), 35.9% B-chamigrene (VII), 19.5% achamigrene (VIII).

(5) 565 g.: B.P. 72-84 C./0.5 mm.: 11 3 115130; sp. gr. C./25 C. 0.9310; v.p.c. (A-l): 21.7% fi-chamigrene (VII), 68.2% u-chamigrene (VHI), 7.9% unknown hydrocarbon, 2.1% cuparene.

(6) 48.8 g.: B.P. 84-90 C./0.5 mm.: m; 1.5150; v.p.c. (A-l): 61.9% u-chamigrene (VIII), 118.0% (formate ester), 20.1% (formate ester).

(7) 61.0 g. residue.

The redistillation of fractions 3, 4 and 6 will give more 18 material similar to fraction 5, the desired chamigrenes.

The product of the reaction contains approximately 10% of 1,4,11,1l-tetramethylbicyclo[5.4.0]undeca-3,7-diene (X) which is diflicult to detect as it has the same retention time by v.p.c. (A-l) as a-chamigrene (VI'II). v.p.c. (A-4) shows this component as a shoulder on the main peak (a-chamigrene). 'Isomerization of a small sample of the product according to Example 1 converts hydrocarbon X to the known hydrocarbon 2,2,3,7-tetramethyltricyclo[5.2.2.0 ]undec 3 ene (XI) and the chamigrenes (VII and VIII) to the tricyclic hydrocarbons A and B, Example 1. The components are now easily analyzed by v.p.c. (A-l).

'Pure samples of 3- and a-chamigrenes (VII and VIII) are prepared from the above fraction 5 as described in Example 2. The IR, NMR and mass spectral data are identical to the data given for the pure materials in Example 2.

EXAMPLES 5-20 Thujopsene (IV) or the chamigrenes (VII and VHI) are isomerized with the reagents and under the conditions given in the table below. Fifty (50) ml. benzene and 100 ml. water are added and the benzene layer separated. The benzene layer is washed 2X50 ml. of water, neutralized with 10% sodium bicarbonate and washed with water. The benzene is removed by distillation under reduced pressure and the residual crude hydrocarbons are vacuum distilled at 0.5 mm. using a distillation head. The distilled hydrocarbons are analyzed by v.p.c. (A-l). The relative retention times to thujopsene (IV) of the main components are as follows: 0.67, unknown hydrocarbon; 0.82, unknown hydrocarbon; 0.97, 2,2,3,7-tetramethyltricyclo [5.2.2.0 ]undec-3-ene (XI), 1.00, thujopsene (IV); 1,12, tricyclic hydrocarbon A; 1.27, tricyclic hydrocarbon B; 1.39, B-chamigrene (VII); 1.54, 1,4,11,11-tetramethylbicyclo[5.4.0]undeca-3,7-diene (X); 1.55, a-chamigrene (V111); 1.69, 4,7,11,1l-tetrarnethylbicyclo[5.4.0]undeca- 1,3-diene; 2.01, cuparene.

In order to establish the amounts of the hydrocarbons (X) and (VIII), a 5 g. sample of the distilled hydrocarbons is isomerized using 5 g. acetic acid and 2 g. polyphosphoric acid for 3 hours at 40 C. The sample is worked up as described above and analyzed by v.p.c. (A-l). The increase in the peak (relative retention time 0.97) corresponding to 2,2,3,7 tetramethyltricyclo[5.2.2.0 undec-3-ene (X1) is the amount of 1,4,11,11-tetramethylbicyclo[5.4.0]undeca-3,7-diene (X) in the sample before this isomerization. Subtracting the amount of (X) from the peak (retention time 1.541.55) of (X) and (VIII) gives the amount of a-chamigrene (VIII) in the original sample.

The desired products in the table below are the chamigrenes (VII and VIII) and the tricyclic hydrocarbons A and B. The unidentified hydrocarbons, 4,7,11,11-tetramethylbicyclo[5.4.0]undeca-1,3-diene and cuparene are all included in the table below under other hydrocarbons.

Reaction condition of- Yield, percent; Analysis of distilled hydrocarbons, percent Dis- Other Thujopstilled hydroene (IV), Temp, Time, hydro- Rescarbons, Ex. grams Isomerization regents, grams C. hrs. carbon idue XI IV A B VII X VIII percent;

5 50.0 6.0 acetic acid,4.6 iormicacid 1 96.0 2.0 23.2 15.4 46.5 14.9 6-.---- 50.0 5.0 acetic acid, 1.0 oxalic acid 100 1 96.0 2.0 2. 9 2.4 27.4 10.1 53.3 3.9 7 30.0 30.0 aicei: a)cid, 12.0 phosphoric 40 3 92.0 5.0 2.3 25.0 22.1 40.9 9.7

aci 8 30.0 30.0 agitligoz aycid, 12.0 phosphoric 40 3 93.0 4.0 7.0 5.2 18.0 6.0 11.3 45.8 6.7

8.01 9-..-..: 30.0 30.0 acetic agid, 12.0 poiy- 40 3 90.0 7.0 11.0 27.6 41.3 8.9 11.2

phosphoric acid 10-.-; 30.0 30.0 acetic acid, 0.3 oly- 40 24 84.0 13.0 .23.; 26.9 35:33:: 18.3 7.8 43.8 3.2

phosphoric acid 115%).- 11...: 30.0 30.0 acetic acid, 0.6 poly- 40 3 93.3 0.7 2 2 ..:::::..::r 28.8 14.9 52.4 1.7

phosphoric acid (115%):

Reaction condition 01- Yield, percent Analysis of distilled hydrocarbons, percent Dis- Other Thujopstilled hydroene (IV), Tcmp., Time, hydro- Rescarbons, Ex. grams Isomerlzation regents, grams C. hrs. carbon idue XI IV A B VII X VIII percent 12..... 30.0 30.0 acetic acid, 2.4 poly- 40 3 89.0 8.0 11.4 16.4 36.9 24.3 11.0

phosphoric acid (115%). 13-.- 30.0 30.0 ethylene dichloride, 12.0 40 8 90.0 7 5.4 5.0 12. 17. 0 7.2 45. 0 7. 3

polyphosphoric acid (115%). 14 50.0 9.0 formic acid (50%) 90 86.0 14.0 7.8 2.0 18.3 14.2 41.8 15.0 15. 30.0 30.(%5a9c e3tic acid, 12.0 sulfuric acid 40 3 93. 0 7.0 83.3 21. 6 28.9 7.1 9. 1 16 30. 0 30.0 ag big acid, 12.0 perchlorlc 40 3 90. 0 7. 0 16.7 30. 1 43. 5 2. 1 7. 6

861 17..--.. 50.0 acetic 5.0m 50 1 08.0 30. 0 11. 1 10. 1 23. 7 30. 1 25. 0

Chamigrenes 18-....- 30.0 30.0acetieac1d, 12.0 poly- 40 3 95.0 5.0 13.5 22.9 35.9 15.9 11.8

phosphoric acid (115%). 19 30.0 30zgsacetic acid, 12.0 sulfuric acid 40 3 90.0 7.0 18.6 28. 2 42.8 10.4 20 80.0 30.0 acetic acid, 12.0 perchloric 40 3 89.0 9. 0 15. 2 28.4 46. 7 2. 1 7.6

acid (70%).

EXAMPLE 21 drocarbons, 11.7% hydrocarbons A (Example 1), 17.2% 30 hydrocarbons B (Example 1), 8.5 consisting of four 4-aceto-6,8a-ethano 1,1,6-trimcthyl 1,2,3,5,6,7,8,8aoctahydronaphthalene (isomer G, V) and isomers (A- Into a reaction flask equipped with an agitator, thermometer, feeding funnel and a condenser is charged 480 g. of polyphosphoric acid (115%). Acetic anhydride, 400 g. is fed in with agitation over a 5-minute period and the temperature increases from 25 C. to 50 C. The batch is cooled to 25 C. and 200 ml. methylene dichloride is added. Thujopsene (IV), (98%), 204 g., is fed in over a 10-minute period with agitation and slight cooling at 25 C. and the batch is agitated at 25 C. for 2 hours. The temperature is raised to 50 C. over a 10 minute period and the batch is agitated at 50 C. for 2 hours. The batch is poured on to 1000 g. of agitated ice. The temperature is raised to 50 C., agitated for minutes and allowed to settle. The oil layer is separated and the aqueous layer is extracted 3X50 ml. of methylene dichloride. The combined oil and extracts are washed 2x50 ml. of water and made alkaline to phenolphthalein using 10% sodium carbonate. The methylene dichloride is distilled off at atmospheric pressure to a pot temperature of 70 C. Benzene, 100 ml. is added and the batch is washed neutral with salt water.

The benzene is distilled off under reduced pressure leaving 243 g. of crude. The crude is analyzed by v.p.c. (A-2): 32.0% consisting of 9 hydrocarbons, 29.2% consisting of 5 isomeric tricyclic 0 1-1 0 ketones, designated as isomers A, B, C, D, E and F, 38.8% 4-aceto-'6,8aethano-1,1,6 trimethyl 1,2,3,5,6,7,=8,8a-octahydronaphthalcne (V), designated as isomer G.

The crude is vacuum distilled to remove the residue using a distillation still head to give 171 g. of distillate, B.P. 68l48 C./0.2 mm. and 65 g. of residue.

The distillate is redistilled using a 6-inch column packed with glass helices and the following fractions are collected:

(1) 53.2 g.; B.P. 86-105 C./0.2 mm.; n 1.5080; v.p.c. (A-2): 18.8% consisting of 3 unidentified hydrocarbons, 28.6% hydrocarbons A (Example 1), 33.8% hydrocarbons B (Example 1), 3.5% consisting of three unidentified hydrocarbons, 9.8% isomers A-F, 5.5% isomer G (V).

(2) 20.6 g.; B.P. 105-115" C./0.2 mm.; n 1.5133; v.p.c. (A-2): 3.3% consisting of two unidentified hyunidentified hydrocarbons, 40.3% isomers A-F, 18.8% isomer G (V).

(3) 94.5 g.; B.P. 115-140 C./0.2 mm.; n 1.5212; sp. gr. 25 C./25 C. 1.0125; carbonyl value (oximation) 181.9; v.p.c. (A-2): 43.7% isomers A-F, 56.3% isomer G (V).

(4) 3.5 g. residue.

Fraction 3 (a mixture of isomers A-G) is one of the desired products and is further analyzed as follows: v.p.c. (A-3): 7.9% A, 6.8% B, 3.5% C, 8.5% D (4-aceto- 2,2,3,7 -tetramethyltricyclo[5.2.2.0' ]undec-3-ene, V1), 7.9% E, 13.2% F and 51.8% G. (V).

IR (C) (v, neat, max.): 2945 (s.), 2925 (s.), 2862 (s.), 1750 (w.), 1737 (m.), 1708 (s.), 1730 s.), 1592 (m.), 1455 (s.), 1385 (m.), 1365 (s.), 1355 s.), 1278 (W.), 1240 (s.), 1220 (m.), 1175 (m.), 1158 (m.), 1025 (W.), 998 (W.), 940 (w.), 900 (w.), 800 (w.), 625 (w.), 599 (w.) cmr NMR (60 m hz., -1-, CDC1 9.22, 9.15, 9.12, 9.08, 9.03, 9.00, 8.97, 8.90, 8.83, 8.77 (ea. 9H, singlets methyl H), 8.73, 8.67, 8.58, 8.42, 8.40, 8.33, 8.30 (ea. 10H, singlets methylene H), 7.98, 7.88, 7.85, 7.80, 7.70, 7.62 (ca. 6 /2, singlets, methyl H on carbonyl plus allylic H), 4.75 (ca. /2 H, broad multiplet, vinylic H): mol. wt. 246 (mass spectra).

In the above NMR the singlets at 9.22, 9.15 and most of the singlet at 7.80 are due to the isomer G (V); the singlets at 9.03, 7.85 and a portion of the singlets at 9.08, 9.00 and a portion of the multiplet at 4.75 are due to isomer F; a portion of the singlets at 9.08, 9.00, 8.97 and 7.80 are due to isomer D (VI); the singlets at 8.90, 7.88 and a portion of singlet 8.83 are due to isomer B; the singlet at 7.98, a portion of the singlets at 8.97, 8.83 and a portion of the multiplet at 4.75 are due to isomer B. Assignment for the isomers C and E can not be made since these isomers have not been obtained in the pure form.

EXAMPLE 22 4-aceto 6,8a-ethano 1,1,6-trimethyl-1,2,3,5,6-,7,8,8a-

octahydronaphthalene (isomer G, V) and isomers (A- A. mixture of tricyclic C H O ketones (isomers A- G), fraction 3, Example 21, 71 g., is vacuum distilled at 0.05 mm., reflux ratio to 1 using a Nestor/Faust 21 distillation column (B). The following fractions are collected:

(1) 4.1 g.; B.P. 60-70 C./0.05 mm.; hydrocarbons-l-isomer A.

(2) 1.3 g.; B.P. 70 C./0.05 mm.; isomer A.

(3) 2.5 g.; B.P. 70-73 C./0.05 mm.; isomers A-t-B.

(4) 2.4 g.; B.P. 73-74 C./0.05 mm.; isomer B.

(5) 2.6 g.; B.P. 74-75 C./0.05 mm.; isomers B+C.

(6) 2.4 g.; B.P. 74-76 C./0.05 mm.;; isomers C-l-D.

(7) 2.4 g.; B.P. 76 C./0.05 mm.; isomer D (VI).

(8) 4.9 g.; B.P. 76-80 C./0.05 mm.; isomer D (VI) +E.

(9) 3.0 g.; B.P. 80-88 C./0.05 mm.; isomer E+F.

(10) 3.4 g.; B.P. 88-90 C./0.05 mm.; isomer F.

(11) 18.8 g.; B.P. 90-92" C./0.05 mm.; isomer F (%)+isomer G (V) (85%).

(12) 17.7 g.; B.P. 92-93" C./0.05 mm.; isomer G (V).

(13) 2.0 g. residue.

Fraction 12 is pure 4-aceto-6,8a-ethano-l,1,6-trimethyl-1,2,3,5,6,7,8,8a-octahydronaphthalene, isomer G (V), and analyzes as follows:

Calcd. for 0 1-1 0: C, 82.87%; H, 10.64%. Found: C, 82.79%; H, 10.71%.

Carbonyl value (oximation), 227.4; n 1.5265; [a] 0 30'; 1, MeOI-I, max. 257 mm. (2 6,745):

NMR (D) (1', p.p.rn., CDCl 7.58 (2 H, singlet, allylic H), 7.70-8.00 (2H, multiplet, allylic H), 7.80 (3H, singlet, carbonyl methyl H), 8.17-9.00 (10H, multiplet, methylene H), 9.15 (3H, singlet, methyl H), 9.20 (6H, singlet, methyl H).

Mass spectrum: 246 mol. wt. 246 (43%), 231 (19%), 218 (31%), 203 (58%) 189 (4%), 175 (14%), 161 (32%), 147 (11%), 133 (14%), 119 (15%), 109 (10%), 107 (9%), 105 (22%), 95 (15%), 93 (10%), 91 (20%), 81 (12%), 79 (12%), 77 (11%), 69 (9%), 67 (9%), 65 (7%), 55 (17%), 53 (10%), 43 (100%), 41 (36%).

IR (C) (v, neat, max.): 2940 (s.), 2920 (s.), 2855 (s.), 1673 (s.), 1588 (m.), 1454 (m.), 1382 (m.), 1345 (m.), 1355 (m.), 1365 (m.), 1280 (w.), 1245 (m.), 1235 (m.), 1175 (m.), 1130 (w.), 940 (w.) cm.

The ethylene thioketal of isomer G (V) is prepared by dissolving 1 g. isomer G (V) in 10 ml. of acetic acid and adding 1.1 ml. of ethanedithiol followed by the addition of 1.1 ml. of boron trifluoride etherate. The mixture is allowed to stand 3 /2 hours at room temperature. 50 ml. of water is added and is extracted 3X25 ml. of hexane. The hexane extracts are washed 2X50 ml. Water, 25 n11. of 5% NaOH, 5 X50 ml. water and are dried over MgSO The hexane is distilled off to give 1.1 g. of the crude crystalline thioketal. The crude is recrystallized twice from 10 ml. of hexane and the crystals vacuum dried. The product analyzes as follows:

M.P. 76-77 C.; mol. wt. 320 (mass spectrum (B)).

NMR (D) (7", CDCI 6.72 (4H, singlet, thioethylene H), 7.5-7.9 (4H, multiplet, allylic H), 8.10 (3H, singlet, methyl H), center at 8.62 10H, broad pattern, methylene H), 9.12 (3H, singlet, methyl H), 9.23 (6H, singlet, methyl H).

IR (C) (v, KBr, max.): 2900 (s.), 2840 (s.), 1453 (s.), 1423 (s.), 1384 (s.), 1370 (s.), 1363 (s.), 1279 (s.), 1240 (m.), 1141 (m.), 1130 (m.), 1085 (w.), 1060 (w.), 1035 (m.), 1019 (m.), 976 (w.), 852 (m.).

The X-ray crystal structure determination establishes the structure of the thioketal as the racernic ethylene thioketal derivative of 4-aceto-6,8a-ethano-l,1,6-trimethylyl-l,2,3,5,6,7,8,8a-octahydronaphthalene (V). Isomer G is regenerated by the method of Corey (E. J. Corey and D. Crouse, J. Org. Chem, 33, 298 (1968)) and which analyzes to give data identical to that given above for fraction 11. Thus, isomer G is 4-aceto-6,8a-ethano- 1,1,6-trimethy1 1,2,3,5,6,7,8,8a octahydronaphthalene (V).

Samples of Isomers A, B, D (VI) and F are prepared in high purity by the preparative v.p.c. (A-l) of the above fractions 2, 4, 7 and 10. Isomers C and E are not obtained in high purity by the preparative v.p.c. (A-l) of any of the above fractions.

The following is the data for the isomers A, B, D and F:

Isomer A Mass spectrum (B): mol. wt. 246 (4%), 231 (2%), 213 (2%), 203 (2%), 191 (4%), 176 (72%), 175 (33%),161 (34%),146(6%),133(9%),l20(34%), 105 95 (13%), 91 (18%), 81 (11%), 79 (9%), 77 (10%), 69 (8%), 55 (15%), 43 (32%), 41 (24%).-

IR (C) (v, neat, max.): 2920 (s.), 2855 (s.), 1712 (s.), 1455 (s.), 1380 (m.), 1360 (s.), 1355 (s.), 1245 (w.), 1260 (w.), 1280 (w.), 1190 (w.), 1165 (m.), 1155 (m.), 1140 (m.), 1115 (w.), 1050 (w.), 960 (w.), 950 (w.), 850 (w.), 820 (m.), 695 (w.), 590 (m.) cm.-

NMR (1', CDCI 4.23 (1H, singlet, vinylic H), 7.17- 7.82 (3H, multiplet, allylic H), 7.98 (3H, singlet, carbonyl methyl H), 8.33-9.03 (10H, multiplet, methylene H), 8.80 (3H, singlet, methyl H), 8.67 (3H, singlet, methyl H), 8.93 (3H, singlet, methyl H).

Isomer B Mass spectrum (B): mol. wt. 246 (4%), 231 (2%), 218 (74%), 203 (9%), 189 (3%), 175 (24%), 159 (15%), 145 (13%), 133 (19%), 119 (32%), (31%), 91 (18%), 84 (64%), 69 (13%), 55 (14%), 43 (100%).

IR (C) (u, neat, max.): 2930 (s.), 2860 (s.), 1710 (s.), 1660 (w.), 1465 (m.), 1450 (s.), 1380 (m.), 1360 (s.), 1350 (m.), 1240 (m.), 1170 (m.), 1090 (w.), 1050 (w.), 1025 (w.), 980 (w.), 940 (w.), 900 (w.), 825 (m.), 800 (w.), 670 (m.) cm.

NMR (D) ('1', CDCI 4.28 (1H, singlet, vinylic H), 7.25-7.83 (2H, multiplet, allylic H), 7.87 (3H, singlet, carbonyl methyl H), 8.00-8.70 (8H, multiplet, methylene H), 8.72-9.08 (3H, multiplet, methyl H), 8.83 (3H, singlet, methyl H), 8.90 (6H, singlet, methyl H).

Isomer D Mass spectrum (B): mol. wt. 246 (16%), 231 (35%), 218 (6%), 213 (3%), 203 (25%), 189 (5%), 175 (7%), 161 (11%), 147 (11%), 137 (11%), (10%), 133 (17%), 123 (9%), 121 (10%), 119 (17% 109 (13%), 107 (9%), 105 (13%), 95 (15%), 91 (11%), 81 (12%), 79 (8%), 77 (7%), 69 (10%), 55 (14%), 43 (100%), 41 (20%).

IR (C) (v, neat, max.): 2940 (s.), 2860 (s.), 1690 (s.), 1615 (w.), 1560 (s.), 1378 (m.), 1362 (m.), 1350 (m.), 1240 (m.), 1225 (m.), 11205 (m.), cmf

NMR (D) (1', CDCI 7.77 (3H, singlet, carbonyl methyl H), 7.85-8.17 (3H, multiplet, possibly 2 allylis-l-l methine H), 8.28 (3H, vinyl methyl H), 8.28-8.82 (8H, multiplet, methylene H), 8.97 (3H, singlet, methyl H), 9.())0 (3H, singlet, methyl H), 9.07 (3H, singlet, methyl H These data are identical to the values for an authentic sample of 4-acet0-2,2,3,7-tetramethyltricyclo[5.2.2.0 undec-3-ene (VI) prepared from 2,2,3,7-tetramethyltricyclo [5.2.2.0 ]undec-3-ene (XI) (L. E. Friedrich, Dissertation, page 160, University Microfilms, Ann Arbor, Mich., No. 67-8559).

Isomer F Mass spectrum (B): mol. wt. 246 (21%), 231 (48%), 217 (9%), 203 (50%), 189 (23%), 175 (15%), 173 (18%), 159 (22%), 147 (14%), (15%), 133 (19%), 131 (15%), 119 (60%), 105 (33%), 95 (19%), 93

IR (C), (v, neat, max.): 2915 (s.), 2940 (s.), 2558 (s.), 1708 (s.), 1453 (m.), 1387 (w.), 1368 (rm), 1355 (m.), 1220 (w.), 1158 (m.), 810 (w.).

NMR (D) (r, CDCI 4.63-4.88 (1H, multiplet, vinylic H), 7.17-7.92 (3H, multiplet, allylic H or allylic and p to carbonyl H), 7.83 (3H, singlet, carbonyl methyl H), 8.00-8.83 (10H, multiplet, methylene H), 8.98 (3H, singlet, methyl H), 9.03 (3H, singlet, methyl H), 9.07 (3H, singlet, methyl H).

EXAMPLE 23 4-aceto-6,8a-ethano-1,1,6-trimethyl 1,2,3,5,6,7,8,8a-octahydronaphthalene (isomer G, V) and isomers (A-F) Into a reaction flask equipped with an agitator, thermometer, feeding funnel and a condenser is charged 480 g. of polyphosphoric acid (115% Acetic anhydride, 400 g., is fed in with agitation over a 5-minute period. The temperature increases from 25 C. to 50 C. The batch is agitated 5 minutes, cooled to 45 C. and 2. 04 g. thujopsene (IV) (98%) is fed in over a 15-minute period at 45 C. The batch is agitated at 45 C. for 2 hours and poured on to 1000 g. of ice. The batch is agitated at 50 C. for 0.5 hour and allowed to settle. The oil layer is separated and the aqueous layer is extracted 3X50 ml. benzene. The combined oil and extracts are washed 2X50 ml. of water, made alkaline to phenolphthalein with Na CO and washed neutral with salt water. The benzene is distilled off under reduced pressure to give 241 g. of crude ketones which analyze by v.p.c. (A-l): 19.8% consisting of 6 hydrocarbons, 38.5% ketones, isomers A-F and 41.7% isomer G (V).

The crude is vacuum distilled using a distillation still head and the following fractions collected:

(1) 42.5 g.; B.P. 90-115" C./0.5 mm.; n 1.5081; v.p.c. (A-2): consisting of two unidentified hydrocarbons, 24.1% hydrocarbons A (Example 1), 28.7% hydrocarbons B (Example 1), 3.8% unidentified hydrocarbons (3 components), 19.0% isomers A-F, 9.3% isomer G (V).

(2) 11.5 g.; B.P. 105-118 C./0.5 mm.; n3 1.5130; v.p.c. (A-2): 3.4% two unidentified hydrocarbons, 8.6% hydrocarbons A (Example 1), 11.8% hydrocarbons B (Example 1), 6.1% four unidentified components, 44.3% isomers A-F, 25.8% isomer G (V).

(3) 92.5 g.; B.P. 118-150" C./0.5 mm.; n 1.5186; sp. gr. C./25 C. 1.0132; carbonyl value (oxima tion) 185.0; v.p.c. (A-2): 0.7% unidentified component, 50.9% isomers A-F, 48.4% isomer G (V).

(4) 90 g. residue.

Fraction 3 is one of the desired products of this example and the ketone analyze by v.p.c. (A-3): 3.7 isomer A, 7.3% isomer B, 1.1% isomer C, 9.7% isomer D (4 aceto 2,2,3,7-tetramethyltricyclo[5.2.2.0 ]undec-3- ene (VI)), 3.7% isomer E, 12.4% isomer F and 55.6% isomer G (4-aceto6,8a-ethano-1,1,6-trirnethyl-1,2,3,5,6, 7,8,Sa-octahydronaphthalene (V)). The IR, NMR and mass spectral data are identical to the data given for fraction 3, Example 21. The material can be processed to pure isomer G (V) as described in Example 22.

EXAMPLE 24 4-aceto-6,8a-ethano-1,1,6-trimethyl-1,2,3,5,6,7,8,8a-octahydronaphthalene (isomer G, V) and isomers (A-F) Two hundred forty (240) grams of polyphosphoric acid (115%), 200 g of acetic anhydride, 102 g. of methylene dichloride and 102 g. of tricyclic C H hydrocarbons A and B (IX), fraction 3, Example 1, are processed as described in Example 21.

The crude amounts to 124 g. and analyzes as follows: v.p.c. (A-2): 21.8% consisting of 6 hydrocarbons, 32.2% ketones, isomers A-F and 46% isomer G (V).

The crude is vacuum distilled using a distillation still head and the following fractions are collected:

(1) 28.0 g.; B.P. -123 C./0.5 mm.; 11 1.5092; v.p.c. (A-2): 6% consisting of 3 unidentified hydrocarbons, 29.7% hydrocarbons A, (Example 1), 35.3% hydrocarbons B (Example 1), 3.7% consisting of 2 unidentified hydrocarbons, 15.5 isomers A-F, 3.6% isomer G (V).

(2) 77.0 g.; B.P. 123-165 C./0.5 mm.; n 1.5230; sp. gr. 25 C./25 C. 1.0148; carbonyl value (oximation) 198.0; v.p.c. (A-2): 3.0% (3 unidentified components), 42.5% isomers A-F, 54.4% isomer G (V).

(3) 17.0 g. residue.

Fraction 2 is one of the desired products of this example and the ketones analyze by v.p.c. (A-3): 10.3% isomers A and B, 5.5% isomer C, 2.1% isomer D (4 aceto 2,2,3,7-tetramethyltricyclo[5.2.2.0 ]undec-3- ene, V1), 5.3% isomer E, 15.8% isomer F, 49.5% isomer G (4-aceto-6,8a-ethano-1,1,6 trimethyl 1,2,3,5,6,7,8,8aoctahydronaphthalene (V). The IR, NMR and mass spectral data are identical to the data given for fraction 3, Example 21.

The material can be processed to pure isomer G (V) as described in Example 22.

EXAMPLE 25 4-aceto-6,8a-ethano-1,1,6-trimethyl-1,2,3,5,6,7,8,8a-octahydronaphthalene (isomer G, V) and isomers (A-F) Two hundred forty (240) grams of polyphosphoric acid, 200 g. of acetic anhydride, 102 g. of methylene dichloride and 102 g. of 8- and ct-chamigrenes (VII and VIII), fraction 3, Example 2 are processed as described in Example 21.

The crude amounts to 129 g. and analyzes as follows: v.p.c. (A-2): 28.7% hydrocarbons (6 components), 35.1% isomers A-F, 36.2% isomer G (V).

The crude is vacuum distilled using a distillation head to give the following fractions:

(1) 29.0 g.; B.P. 75-118 C./0.5 mm.; 11 1.5079; v.p.c. (A-2): 21.6% (2 unidentified hydrocarbons), 30.7% hydrocarbons A (Example 1), 33.9% hydrocarbons B (Example 1), 10.3% isomers A-D.

(2) 54.5 g.; B.P. 118-170 C./0.5 mm.; n 1.5188; sp. gr. 25 C./25 C. 1.0154, carbonyl value (oximation) 191.1; v.p.c. (A-2): 0.9% (unidentified hydrocarbons), 45% isomers A-F, 53.5% isomer G (V).

(3) 36.0 g. residue.

Fraction 2 is one of the desired products of this example and analyzes by v.p.c. (A-3): 5.2% isomer A, 9.2% isomer B, 6.9% isomer C, 13.3% isomer D (4-aceto- 2,2,3,7 tetramethyltricyclo[5.2.2.0 ]undec-3-ene, V1), 7.4% isomer E, 9.2% isomer F, 44.0% isomer G (4 aceto 6,8a ethano-1,1,6-trimethyl-1,2,3,5,6,7,8,8aoctahydronaphthalene, V). The IR, NMR and mass spectral data are identical to the data given for fraction 3, Example 21.

The material can be processed to pure isomer G (V) as described in Example 22.

EXAMPLE 26 4-aceto-6,8a-ethano-1,1,6-trimethyl-l,2,3,5,6,7,8,8a-octahydronaphthalene (isomer G, V) and isomers (A-F) Two hundred forty (240) grams of polyphosphoric acid, 200 g. of acetic anhydride, 102 ml. of methylene dichloride and 102 g. of hydrocarbons A and B (IX), fractions 5, Example 3, are processed as described in Example 21.

The crude amounts to 117.5 g. and analyzes as follows: v.p.c. (A-2): 37.4% consisting of 6 hydrocarbons, 25.3% isomers A-F, 37.3% isomer G (V).

The crude is vacuum distilled using a distillation still head to give the following fractions:

(1) 36.0 g.; B.P. 85-113 C./0.5 mm.; n 1.5108; v.p.c. (A-2): 3.9% unidentified hydrocarbon, 35.7% hydrocarbons A (Example 1), 42.8% hydrocarbons B (Example 1), 5.3% consisting of three unidentified components, 6.2% isomers A-F, 6.0% isomer G (V).

(2) 4.5 g.; B.P. 113-121 C./0.5 mm.; n 1.5124; 1.5124; v.pc (A-2): 02% unidentified hydrocarbon, 24.2% hydrocarbons A and B, 12.8% consisting of 4 unidentified components, 37.2% isomers A-F, 25.6% isomer G (V).

(3) 53.5 g.; B.P. 121-143C./0.5 mm.; n 1.5214; sp. gr. 25 C./25 C. 10145; carbonyl value (oximation) 200.8; v.p.c. (A-2): 1.7% consisting of three unidentified components, 40.6% isomers A-F, 57.8% isomer G (V).

(4) 7.0 g.; B.P. 143-153 C./0.5 mm.; n 1.5318; v.p.c (A-Z): 174% isomers A-F, 445% isomer G (V), 38.1% consisting of 2 high boiling components.

(5) 14.0 g. residue.

Fraction 3 is the desired product and the ketones analyze by v.p.c. (A-3): 8.3% isomer A, 9.9% isomer B, 1.0% isomer C, 0.4% isomer D (4-aceto-2,2,3,7-tetramethyltricyclo[5.2.2.0 ]undec-3-ene, V1), 7.7% isomer E, 15.3% isomer F, 57.4% isomer G (4-aceto-6,8aethano 1,1,6-trirnethyl 1,2,3,5,6,7,8,8a-octa-hydronaphthalene, V). The IR, NMR and mass spectral data are identical to that given for fraction 3, Example 21. The material can be processed to pure isomer G as described in Example 22.

EXAMPLE 27 4-aceto-6,8a-ethano-1,1,6-trimethyl-1,2,3,5,6,7,8,8a-octahydronaphthalene (isomer G, V) and isomers (A-F) Two hundred forty (240) grams of polyphosphoric acid (115%), 200 g. of acetic anhydride, 202 ml. of methylene dichloride and 102 g. of ocand B-chamigrenes (VII and VIII), fraction 5, Example 4, are processed as described in Example 21.

The crude amounts to 120 g. and analyzes as follows: v.p.c. (A-2): 39.2% consisting of 7 hydrocarbons, 31.6% isomers A-F, 29.0% isomer G (V).

The crude is vacuum distilled using a distillation still head and the following fractions are collected:

1 30.5 g.; B.P. ss-103c./0.s mm.; n 1.509s; v.p.c (A-2): 21.3% consisting of 3 unidentified hydrocarbons, 27.9% hydrocarbons A (Example 1), 31.2% hydrocarbons B (Example 1), 11.0% consisting of 2 unidentified components, 8.5% isomers A-D.

(2) 14.5 g.; B.P. 103-120 C./0.5 mm.; 21 1.5130; v.p.c (A-2): 5% consisting of 2 unidentified hydrocarbons, 24.2% hydrocarbons A and B (Example 1), 13.9% consisting of 3 unidentified components, 35.7% isomers A-F, 20.1% isomer G (V).

(3) 46.0 g.; B.P. 120-168 C./0.5 mm.; 21 1.5222; sp. gr. 25 C./25 C. 1.0119 8; carbonyl value (oximation) 174.3; v.p.c. (A-2): 3.6% consisting of 5 unidentified components, 47.2% isomers A-F, 49.2% isomer G.

(4) 28.0 g. residue.

Fraction 3 is the desired product and the ketones analyze by v.p.c. (A-3): 4.6% isomer A, 8.3% isomer B, 5.1% isomer C, 14.9% isomer D (4-aceto2,2,3,7-tetramethyltricyclo[5.2.2.0 ]undec-3-ene, V1), 7.1% isomer E, 11.4% isomer F, 48.6% isomer G (4-aceto-6,8a ethano 1,1,6 trimethyl-1,2,3,5,6,7,8,8a-octahydronaphthalene, V). The IR, NMR and mass spectral data are identical to that given for fraction 3, Example 21.

Pure isomer G (V) is obtained from this material as is described in Example 22.

EXAMPLE 28 Mixture of tricyclic C H O ketones containing acetylcedrene (II) enriched in 4-aceto-6,8a-ethano-1,1,6-trimethyl-1,2,3,5,6,7,8,8a-octahydronaphthalene (isomer G, V).

Two hundred forty (240 grams of polyphosphoric acid (115 200 g. of acetic anhydride, 202 ml. of methylene dichloride and 102 g. of hydrocarbons, v.p.c. (A-l): 17.9% a-cedrene/ (I), 13.7% 2,2,3,7-tetramethyltricyclo [5.2.2.0 ]undec-3-ene (XI), 42.2% hydrocarbons A, 26.5% hydrocarbons B from fraction 4, Example 3, are processed as described in Example 21.

There is obtained 115 g. of crude which analyzes by v.p.c. (A-2) as follows: 36.1% hydrocarbons (6 components), 8.8% isomers A-C, 13.4% acetylcedrene (II) and isomer D (VI), 13.5% isomer E and F, 26.6% isomer G (V).

The crude is vacuum distilled using a distillation still head and the following fractions are collected:

(1) 33.0 g.; B.P. 105 C./0.5 mm.; 11 1.5071; v.p.c (A-2): 23.5% a-cedrene (I), 01.7% 2,2,3,7-tetramethyltricyclo[5.2.2.0 ]undec-3-ene (XI), 28.1% hydrocarbons A (Example 1), 25.3% hydrocarbons B (Example 1) 1.3% consisting of 2 unidentified components, 3.5% isomers A and B, 2.7% acetylcedrene (II) and isomer D (VI), 3.9 isomers E-G.

(2) 6.0 g.; B.P. -123C./0.5 mm.; 11 1.5117; v.p.c. (A-2): 9.2% oc-cedrene (I), 6.2% 2,2.3,7-tetra methyltricyclo[5.2.2.0 ]undec-3-ene (X-I), 19.9% hydrocarbons A (Example 1), 25.4% hydrocarbons B (Example 1), 4.4% consisting of 4 unidentified components, 11.7% isomers A and B, 8.2% acetyl cedrene (II) and 2012161) D (VI), 5.3% isomers E and F, 9.8% isomer (3) 62.4 g.; B.P. 123156 C./0.5 mm.; n 1.5189; sp. gr. 25 C./25 C. 1.0129; carbonyl value (oximation) 186.9; v.p.c. (A-2): 17.2% isomers A and B, 14.8% acetylcedrene (II) and isomer D (VI), 18.5% isomers E and F, 49.4% isomer G (V).

(4) 11.0 g. residue.

Fraction 3 is the desired product and the ketones analyze by v.p.c. (A-3): 4.2% isomer A, 5.0% isomer B, 17.8% acetylcedrene (II) and isomer D (VI), 7.1% isomer E, 14.4% isomer F and 511.5% isomer G (V).

The IR, NMR and mass spectral data is compatible with a mixture of the above ketones.

EXAMPLE 29 Mixture of tricyclic C H O ketones containing acetylcedrene, 4 aceto-6,8a-1,1,6-trimethyl-1,2,3,5,6,7,8,8aoctahydronaphthalene (isomer G, V) and isomers Four hundred eighty (480) grams of polyphosphoric acid 400 g. of acetic anhydride, 200 ml. of ethylene dichloride and 204 g. of cedarwood hydrocarbons (v.p.c. (A-l): 0.7% unknown C H hydrocarbon, 37.0% a-cedrene (I), 7.4% fi-cedrene (III), 50.7% thujopsene (IV), 4.7% thujopsene isomers) is processed as described in Example 21, except ethylene dichloride is used for the extractions instead of methylene dichloride.

The crude amounts to 219 g. which analyzes as follows: v.p.c. (A-2): 28.7% hydrocarbons (5 components), 6.4% isomers A, B and C, 33.8% acetylcedrene (II), and isomer D (VI), 11.1% isomers E and F, 21.3% isomer G (V).

The crude is vacuum distilled using a distillation still head and the following fractions are collected:

(\1) 37.5 g.; B.P. 85-105 C./0.5 mm.; n 1.5031; v.p.c. (A-2); 100% hydrocarbons (8 components).

(2) 13.0 g.; B.P 105-@113" C./0.5 mm.; n 1.5077; v.p.c. (A-2): 61.8% hydrocarbons (6 components), 38.2% ketones (acetylcedrene (II), isomers A-G).

(3) 9.0 g.; BJP 113-120 C./0.5 mm.; 21 1.5113; v.p.c. (A-2): 35.8% hydrocarbons (6 components), 64.2% ketones (acetylcedrene (H), isomers A-G).

(4) 99.5 g.; B.P. 120-168 C./0.5 mm.; 11 1.5195; sp. gr. 25 C./25 C. 1.0035; carbonyl value (oxirnation) 190.1; v.p.c. (A-Z): 4.8% hydrocarbons (4 comioncigts), 95.2% ketones (acetylcedrene (II), isomer (5) 10.0 g.; B.P. 168-180" C./0.5 mm.; n 1.5286; v.p.c. (A-l): 40% ketones (acetylcedrene (II), isomers A-G), 60% (high boiling components).

(6) 47.0 g. residue.

The product, fraction 4, is the usual product obtained by the acetylation of cedarwood hydrocarbons which analyzes by v.p.c. (A-3) as follows: 5.3% isomer A, 10.0% isomer B, 45.5% acetylcedrene (II) and isomer D (VI), 7.3% isomer E, 12.0% isomer F, 19.9% isomer G (V) The IR, NMR and mass spectra data is compatible with a mixture of the above ketones.

EXAMPLE 30 4-aceto-6,8a-ethano-1,1,6-trimethyl-1,2,3,5,6,7,8,8a-octa hydronaphthalene (isomer G, V) and isomers (A- F) A mixture of the tricyclic hydrocarbons A and B (IX), Example 1, fraction 3 is vacuum distilled at 5 mm. using a Nester/Faust column (E) and a reflux ratio of to 1 to give hydrocarbons A and hydrocarbons B. The analysis of the hydrocarbons is the same as reported in Example 1.

(A) Polyphosphoric acid, 22 g., acetic anhydride, 18 g., methylene dichloride, 9 ml. and hydrocarbons A, 9 g., are processed as described in Example 21.

The crude amounts to 11 g. and analyzes as follows: v.p.c. (A-2): 27.3% consisting of 9 hydrocarbons, 33.5% isomers A-F, 39.2% isomer G (V).

The crude is vacuum distilled using a micro distillation still head and the following fractions are collected:

(1) 2.5 g.; B.P. 83-110 C./0.4 mm.; h 1.5056; v.p.c. (A-2): 10.3% consisting of 4 unidentified hydrocarbons, 38.5% hydrocarbons A (Example 1), 45.0% bydrocarbons B (Example 1), 2.1% consisting of 2 unknown components, 4.0% isomer A.

(2) 1.0 g.; B.P. 110-118 C./0.4 mm.; 11 1.5135; v.p.c. (A-2): 30.2% hydrocarbons A and B (Example 1), 13.5% consisting of 6 unknown components, 41.5% isomers A- F; 16.1% isomer G (V).

(3) 5.5 g.; B.P. 118-150 C./0.4 mm.; 11 1.5230; carbonyl value (oximation) 191.3, v.p.c. (A-2): 2.1% consisting of 3 unknown components, 45.7% isomers A-F, 52.2% isomer G (V).

(4) 1.5 g. residue.

.Fraction 3 is the desired product of isomers and the ketones analyze by v.p.c. (A-3): 18.2% isomer A, 7.8% isomer B, 4.3% isomer C, 1.3% isomer D (V1), 7.0% isomer E, 12.7% isomer F and 48.7% isomer G (V).

' The NMR, IR and mass spectral data on the products are compatible with the data for a mixture of the ketones.

Pure isomer G (V) is prepared by preparing larger quantities of the product and proceeding as described in Example 21.

(B) Polyphosphoric acid, 22 g., acetic anhydride, 18 g., methylene dichloride 9 m1., and hydrocarbons B, 9 g., are processed as described in Example 21.

The crude, containing a small amount of benzene, amounted to 12 g. and analyze as follows: v.p.c. (A-2): 21.2% consisting of 9 hydrocarbons, 30.6% isomers A-F, 48.2% isomer G (V).

The crude is vacuum distilled using a micro distillation still head and the following fractions are collected:

(*1) 1.5 g. B.P. -105 C./0.7 mm.; a 1.5090; v.p.c. (A-Z): 75% 3 unidentified hydrocarbons, 30.7% hydrocarbons A (Example 1), 35.2% hydrocarbons B (Example 1), 5.6% consisting of 4 unknown components, 11.6% isomers A-F, 9.3% isomer G (V).

(2) 1.0 g.; B.P. 105-120 C./0.7 mm.; n 1.5150; v.p.c. (A-2): 1.9% 3 unidentified hydrocarbons, 15.4% hydrocarbons A (Example 1), 20.5% hydrocarbons B (Example 1), 9.8% consisting of 4 unknown components, 29.2% isomers A-F, 23.2% isomer G (V).

(3) 5.5 g.; B.P. l20-158 C./0.7 mm.; 11 1.5235; carbonyl value (oximation) 202.7; v.p.c. (A-2): 34.0% isomers A-F, 65.9% isomer G (V).

(4) 1.5 g. residue.

Fraction 3 is the desired product of isomers and the ketones analyze by v.p.c. (A-3): 9.4% isomer A, 4.5% isomer B, 5.4% isomer C, 0.2% isomer D (V1), 6.5% isomer E, 12.2% isomer F and 61.8% isomer G (V).

The IR, NMR, and mass spectral data are compatible with the data for a mixture of the ketones.

Pure isomer G (V) is prepared by preparing larger quantities of the product and proceeding as described in Example 21.

EXAMPLE 31 Acetylcedrene (11) Four hundred eighty (480) grams of polyphosphoric acid, 400 g. of acetic anhydride, 200 g. of methylene dichloride and 204 g. of a-cedrene (I) (prepared as described in Example 4) are processed as described in EX- ample 21 except the agitation period at 50 C. is increased from 2 hours to 3 hours.

The crude acetylcedrene amounts to 210' g. and analyzes by v.p.c. (A-2) as follows: 22.5% oa-cedrene, 77.5% consisting of 59.5% acetylcedrene (II) and 18.0% of five isomeric C H O ketones.

The crude is vacuum distilled using a 6" column packed with glass helices and the following fractions are collected:

(1) 66.0 g.; B.P. 80-90 C./0.4 mm.; n 1.5008; v.p.c. (A-2): 86.5% u-cedrene (I), 8.8% acetylcedrene, (II).

(2) 5.0 g.; B.P. -98 C./0.4 mm.; 11 1.5135; v.p.c. (A-2): 12.8% a-cedrene (I), 1.3% unidentified hydrocarbons, 85.5% consisting of 64.0 acetylcedrene (II) and 21.9% isomeric 0 11 0 ketones.

(3) 89.0 g.; B.P. 98-105 C./0.4 mm.; n 1.5169, sp. gr. 1.0024; carbonyl value (oximation) 207.0; v.p.c. (A-2): 80.9% acetylcedrene (II), 19.1% consisting of 4 C H O isomeric ketones.

(4) 5.0 g.; B.P. 105-115 C./0.4 mm.; 11 1.5175; v.p.c. (A-2): 60.0% acetylcedrene (II), 40.0% consisting of 5 isomeric C1'1H26O ketones (5) 35.0 g. residue.

Pure acetylcedrene (II) is obtained by the redistillation of fraction 3 above using a Nestor/Faust distillation column (B) at 0.01 mm. and a reflux ratio of 30 to 1. The pure material analyzes as follows: B.P. 84-86 010.01 mm.; carbonyl value (oximation) 216.0; n 1.5152; sp. gr. 25 C./25 C. 1.0029.

Mass spectrum (B): 246 mol. wt. (11%), 231 (17%), 203 (9%),175 (4%),162(5%), 161 (36%),148 (6%), 147 (17%), 146 (2%), 145 (2%), 136 (2%), 135 (9%), 133 (4%), 123 (8%), 121 (8), 119 (20%), 109 (4%), 107 (2%), 105 (14%), 100 (8%), (2%), 93 (4%), 91 (9%), 81 (5%), 79 (4%), 77 (5%), 69 (20%), 67 (3%), 56 (3%), 55 (10%), 53 (3%), 43

NMR (D) (1', p.p.m., CDCl 7.63 (1H, quartet, J=2 Hz., methine allylic H), 7.80 (3H single, carbonyl methyl H), 8.02, 80.5, 8.08 (5H, singlet-l-multiplet, vinylic methyl H+allylic H), 8.17-8.75 (H, multiplet,

methylene H), .98 (3H, singlet, methyl H), 9.02 (3H, singlet, methyl H), 9.1 (3H, doublet, J=8 Hz., methyl H).

IR (v, neat, max.): 2950 (s.), 2865 (s.), 2825 (w.), 1700 (w.), 1672 (s.), 1600 (111.), 1460 (s.), 1430 (m.), 1415 (w.), 1380 (m.), 1370 (m.), 1355 (s.), 1230 (s.), 1198 (w.), 1160 (w.), 1130 (w.), 1085 (w.), 1020 (W.), 935 (w.), 970 (w.), 640 (w.), 600 (w.), 565 (w.) cm."

EXAMPLE 32 4-aceto-6,8a-ethano-1,1,6-trimethyl-1,2,3,5,6,7,8,8a-octahydronaphthalene (isomer G, V) and isomers (A-F) Into a reaction flask equipped with a gas inlet tube which extends to the bottom of the flask, an agitator, thermometer, feeding funnel and a condenser with drying tube is charged 100 g. of acetic anhydride. 20 g. of boron trifluoride gas is passed in over a 15-minute period with cooling at 25 C. 51 g. of hydrocarbons A and B, fraction 3, Example 1, are added over a 15 minute period at 25 C. and the batch is agitated at 25 C. for 4 hours. The batch is poured onto 100 g. of agitated ice. The batch is warmed to 50 C. and agitated for /2 hour and allowed to settle. The oil layer is separated and the aqueous layer extracted 3X50 ml. of benzene. The combined oil and benzene extracts are washed 2X50 ml. of water, made alkaline to phenolphthalein with 5% NaOH and Washed neutral with salt water. The benzene is distilled otf under reduced pressure leaving 61 g. of crude. The crude analyzes by v.p.c. (A-2): 31.5% hydrocarbons (9 components), 39.6% isomers A-F, 28.7% isomer G (V).

The crude is vacuum distilled using a distillation still head and the following fractions are collected:

(1) 11.5 g.; B.P. 102-114 C./0.5 mm.; 11 1.5030; v.p.c. (A2): 5.0% consisting of 4 unknown hydrocarbons, 25.9% hydrocarbons A (Example 1), 29.8% hydrocarbons B (Example 1), 8.4% consisting of 4 unidentified components, 23.4% isomer A-F isomer G (V).

(2) 7.0 g.; B.P. 114-124 C./0.5 mm.; n 1.5165; v.p.c. (A-2): 1.8% consisting of 4 unknown hydrocarbons, 11.9% hydrocarbon A (Example 1), 15.1% hydrocarbon B (Example 1), 13.3% consisting of 4 unidentified components, 44.8% isomers A-F, 13.3% isomer G (V).

(3) 28.1 g.; B.P. 124-162 C./0.5 mm.; n 1.5241; sp. gr. 25 C./25 C. 1.0191; carbonyl value (oximation) 187.9; v.p.c. (A-2): 6.4% consisting of 4 unidentified components, 61.1% isomers A-F, 34.4% isomer G (V).

(4) 12.0 g. residue.

Fraction 3 is the desired product and the ketones are analyzed by v.p.c. (A-3): 19% isomer A, 6.8% isomer B, 13.5% isomer C, 3.2% isomer D (VI), 7.5% isomer E, 15.3% isomer F and 34.7% isomer G (V).

The IR, NMR and mass spectral data are compatible with the product being a mixture of the above isomers. Pure isomer G (V) can be obtained by processing this material according to Example 21.

EXAMPLE 33 Odor evaluations and comparisons are made on the following materials:

(l) 4-aceto-6,8a-ethano 1,1,6 trimethyl-1,2,3,5,6,7,8, 8a-octahydronaphthalene (V, isomer G), Example 22, fraction 2, 100% isomer G (V).

(2) Acetylcedrene (II), acetylthujopsene mixture, Example 29; 5.3% isomer A, 10.0% isomer B, 45.5% acetylcedrene (II) plus isomer D (VI), 7.3% isomer E,-

12.0% isomer F, 19.9% isomer G (V).

(3) Acetylthujopsene mixture, Example 21, fraction 3, 7.9% isomer A, 6.8% isomer B, 3.5% isomer C, 8.5% isomer D(VI), 7.9% isomer E, 13.2% isomer F, 51.8% isomer G (V).

(4) Aetylcedrene (ID-acetylthujopsene mixture prepared by mixing 7.77 parts of fraction 3, Example 28 30 with 2.23 parts of acetylcedrene (II) of Example 31. Analysis of mixture: 3.3 isomer A, 3.9% isomer B, 36.1% acetylcedrene (II) and isomer D (VI), 5.5% isomer E, 11.2% isomer F, 40.0% isomer G (V).

(5) Acetylcedrene-acetylthujopsene mixture, Example 28; 4.2% isomer A, 5.0% isomer B, 17.8% acetylcedrene (II) and isomer D (VI), 7.1% isomer E, 14.4% isomer F, 51.5% isomer G (V).

(6) Acetylcedrene-acetylthujopsene mixture, prepared by mixing 7.22 parts aeeylcedrene-acetylthujopsene mixture, Example 28, fraction 3, with 2.78 parts isomer G (V), Example 22. Analysis of mixture: 3.0% isomer A, 3.6% isomer B, 12.9% acetylcedrene (II) plus isomer D (GVI(),)5.1% isomer E, 10.4% isomer F, 65.0% isomer (7) Aectylcedrene (II), Example 31; acetylcedrene (II), 0% isomer G (V).

(8) Acetylthujopsene mixture, isomers A-F, prepared as described in Example 22 and combining fractions 1-11: 100% isomers A-F, 0% isomer G (V).

(9) Ambergris.

The odor characteristics and odor comparisons of the above materials, 1 to 9, were studied by preparing a 10% solution in ethanol of each and applying 10 1 of the solutions to smelling blotters and allowing them to evaporate at room temperature. The odors on the blotters were studied over a period of ten days.

Material 1, pure isomer G (V), is a very intense, amber, woody and musk-like odor. It is reminiscent of ambergris, material 9, however, it is sweeter and more tenacious than ambergris. The material compared with material 9, ambergris, is approximately three times stronger than ambergris and lasts ten times longer.

Material 2 has a woody amber odor which is weaker than material 1 by a factor of two (2). The odor is thinner and possesses a more characteristic cedar odor than material 1.

Material 3 has a warm woody, amber and musk odor, slightly Weaker than the pure material 1, but still nearly twice as strong as ambergris, material 9, and lasting ten times longer than ambergris, the material is over twice as strong and less of a cedar odor than material 2.

Material 4 possesses a strong woody amber, musk odor. Material 4 is approximately the same strength as material 3 with a more cedar-like character. Material 4 is nearly twice as strong as material 9 and lasts ten times longer.

Material 5 possesses a woody, amber and musk odor, about the same strength as material 3 with a slightly more cedar-like character.

Material 6 possesses a warm, amber, woody and musklike odor and its odor is very similar to material 1. The material is nearly twice as strong as ambergris, material 9, and lasts ten times longer.

Acetylcedrene (II), material 7, possesses a cedar woody odor having no amber or musk notes. Its odor is not related to ambergris, material 9, and is not of especial interest in erfumery.

Material 8 has a dry weak woody odor with a slight amber note. Its odor cannot be related to ambergris and would be of little value as a perfume material.

EXAMPLES 34-43 A cologne base (Example 34) is prepared using the ingredients listed in Example 34. The materials, l-9, of Example 33 are compounded to the extent of 2% by weight into the cologne base of Example 34 to give the colognes of Examples 354?).

The odor characteristics and fixative properties of the colognes are studied and compared by applying 10 ,ul of 10% ethanolic solutions of the colognes to smelling blotters and observing the odor while allowing the colognes to evaporate at room temperature over approximately twelve (12) hours.

Example- .4; 34 35 36 37 38 39 '10 41 42 43 Undeeyllc aldehyde 2 2 2 2 2 2 2 2 2 2 Cedryl acetate 4 195 195 195 195 195 195 195 195 195 195 Clove bud oil 20 20 20 20 20 20 20 20 20 20 Costus oil 1 1 1 1 1 1 1 1 1 1 Diethyl phthalate 80 60 60 60 60 60 60 60 60 60 Estragon oil. 30 30 30 30 30 30 30 30 30 30 Galbanum 011-. 10 10 10 10 10 10 10 10 10 10 ISobornyl acetate- 30 30 30 30 30 30 30 30 30 3O Laurine extra 1 20 20 20 20 20 20 20 20 20 20 Lavender 38/42.-.. 112 1 12 112 112 112 112 112 112 112 112 362 362 362 362 362 362 362 362 362 362 10 10 10 10 10 10 10 10 10 10 90 90 90 90 9O 90 90 90 90 7 7 7 7 7 7 7 7 7 7 1 1 1 1 1 1 1 1 1 1 Versalide 10 10 10 10 10 10 10 10 10 Vetiver oil bourbon 20 20 20 20 20 20 20 2o 20 Mater-i 1(l00% G) 20 a r 2 (19.9% G) 20 3 (51.8% G) 20 4 (40% G) 20 5 (51.5% G) 20 6 (65.0% G) 20 (0% G 20 8 (0% G) 20 9 (0% G) 20 Total"; 1,000 1, 000 1, 000 1, 000 1, 000 1, 000 1,000 1,000 1, 000 1, 000

1 Registered trademark of Givaudan Corp. for hydroxycitronellal.

2 Registered trademark of Givaudan Corp. for isoeamphyl cyelohexanol. I Registered trademark o! Givandan Corp. for 1,1,4,4,-tetramethyl-fi-ethyl-7-acetyl-1,2,3,-itetrahydronaphthalene.

The cologne base, Example 34, during evaporation had a rather harsh top note and dried out woody and thin. Cologne Examples 35 and 43 have soft bright top notes and their odors had better balance and bouquet. Upon drying out (approximately 12 hours) these two colognes showed improved balance and bouquet. In addition, cologne 35 has a warm woodiness which is considered an even more desirable character than that contributed by the ambergris (Example 43). This demonstrates that the presence of 2% of material 1 produces essentially the same effect as 2% ambergris. Material 1 functions as a good blender and fixative with a more pleasing woody amber odor.

Material 1, isomer G, can be used in fragrances from 0.1 to 10% by weight. Larger quantities may also be used depending upon the type of fragrance and the effect desired.

The colognes of Examples 34, 35 and 36 are compared. Cologne, Example 36, containing material 2, has a more pleasing Woody odor than cologne 34, which is an improvement; however, on dry out the balance and bouquet are lost, whereas cologne 35 still has a pleasing bouquet and better balance which is evidence of improved fixation.

The cologne of Example 37 is compared with the colognes of Examples 34, 35 and 36. Material 3 contributes body and a warm woody nuance to the cologne 37. The top notes are brighter and the colognes dry out with a definite improvement in bouquet and balance over colognes 34 and 36. After twelve hours the bouquet of colognes 37 and 35 are still evident whereas that of the colognes 34 and 36 have disappeared. This result indicates that the presence of 50% isomer G in material 3 produces the same fixative properties as material 1, pure isomer G.

The material 3 may be used in fragrances from 0.1 to 10% by weight. To realize the best fixative function, it should be used at approximately 1% by weight and above.

Material 4 contributes body and a warm woody amber nuance to cologne 38. The top notes are brighter, and as the cologne dries out, an improvement in bouquet and balance is noted. After twelve hours, the bouquet of cologne 38 is still evident but not as outstanding as the colognes 35 and 37. This indicates that mixtures of acetylcedrene containing 40% isomer G are essentially the lowest limit for practical fixative properties in these mixtures.

Material 4 may be used in fragrances from 0.1 to 10%, by weight. However, to realize the best fixative function, it should be used at 2% by weight and above.

Material 5 contributes body and a warm woody amber nuance to the cologne, Example 39, and is similar to the cologne of Example 38. However, as a fixative it performs more like material 3, Example 37. The top notes of the cologne 39 are brighter and as the cologne dries out a definite improvement in bouquet and balance is noted. After twelve hours, the bouquet of cologne 39 is still evident indicating the same fine fixative properties as shown by materials 1, 3 and 9.

Material 5 may be used in fragrances in the same manner as material 3; however, to realize the best fixative function, it should be used at 1% by weight and above.

Material 6 contributes a warm woody amber nuance to the cologne, Example 40, and is an excellent fixative. The cologne top notes are brighter and the fragrance in general seems better balanced with a pleasant bouquet which remains throughout the dry out of approximately twelve hours.

Material 6 may be used in fragrances from 0.5 to 10% by weight. Larger quantities may also be used depending upon the type of fragrance and the effect desired.

The cologne, Example 41, containing material 7, is thin and lacks the Warmth and body that is exhibited by the colognes containing materials 1, 3, 4, 5 and 6. The acetylcedrene, material 7, contributes a cedar Woodiness to the cologne 41 which tends to dilute rather than fortify the fragrance. For this reason, mixtures of acetylcedrene and isomer G, containing less than 40% of isomer G, lack outstanding fixative properties. That is, the odor contribution of acetylcedrene dilutes and hinders the ordor contribution of acetylcedrene dilutes and hinders the odor and fixative properties of isomer G.

Cologne, Example 42, containing material 8 is thin and lacks the warmth and body when compared with colognes 35, 37 and 40. This material contributes a light woody note to the cologne and, like acetylcedrene, tends to dilute rather than fortify the fragrance.

The conclusion is drawn that materials 1 and 3 to 6 are fine odorants and valuable perfume materials and can be used to improve and render more desirable many types of fragrances. These materials are novel and excellent fixatives which function in a similar manner to ambergris,

33 34 but are less expensive and of more stable price than References Cited gi q f c'l UNITED STATES PATENTS a 15 c alme is: 1. A process for the preparation of 4-aceto-6,8a- 30171 9/1970 Hewett 260587 X ethano 1,1,6 1,2,3,5,6,7,8,8a octahydl'o' 5 naphthalene which comprises treating a member of the Sh It t R f Th group consisting of a-chamigrene, fi-chamigrene and a o 0 e Wrangement o ulopsene posium on the chemistry of natural products, Fukuoka, m1xture of aand fi-chamlgrenes Wlth acetic anhydrlde in Japan Oct. 29, 1970.

the presence of polyphosphorlc acid.

2. A process according to claim 1, wherein between 10 LEON ZITVER, Primary Examiner about 1 and 10 moles of acetic anhydride and between about 1 and 5 moles of polyphosphoric acid per mole of SCHWARTZ Asslstant Exammer said member are employed at a reaction temperature CL between about 10 and 100 C. 260586 R 

